Megyn Kelly has fashioned herself as a champion of the #MeToo movement, filling her NBC talk show, “Megyn Kelly Today,” with brave women fighting injustice.

But a former colleague says it’s all an act.

“She’s disrespectful,” Iren Halperin, a Fox News makeup artist for 20 years who retired in 2016, told Page Six. “She’s not for women. She’s extremely mean and rude to women.”

Halperin worked with Kelly in 2009, when the latter co-anchored “America’s Newsroom With Bill Hemmer.” Halperin said that Kelly always got her makeup done at 8 a.m., but showed up 30 minutes early one day and tried to kick a female reporter out of the makeup chair.

“I told her, ‘Please have a seat in the greenroom or start your hair first,’ ” Halperin said.

“And she said, ‘No. I want to get done and want to get done now.’ Megyn snapped her finger and pointed at the reporter and said, ‘You, get out of the chair.’ ”

Eventually, Kelly got her way.

“The next day my boss called me. Megyn went and lied to management and said, ‘[Iren] can’t come in on time because she has child-care issues,’” said Halperin, a mother of three, who started work an hour before Kelly’s scheduled makeup sessions.

Halperin asked to be switched to a different anchor. Another Fox employee interviewed for this story also demanded a reassignment due to Kelly’s attitude. Fox News did not return calls for comment.

“She was difficult and demanding,” Halperin added. “And if you didn’t do what she wanted, she would try to get you in trouble.”

Now, it seems, Kelly is in trouble herself.

Since “Megyn Kelly Today” launched in NBC’s 9 a.m. weekday spot in September, the former Fox anchor — famed for her hard-hitting questions — has been struggling to find her footing in the bubbly world of morning news. Her January Nielsen ratings in the 25-to-54-year-old demographic are nearly 30 percent lower than they were for Tamron Hall and Al Roker’s show when it was in the same time slot last year.

NBC execs are said to be growing weary of Kelly’s drama, such as questioning Jane Fonda’s patriotism in a January monologue.

A high-ranking NBC veteran said that the show atmosphere is so tense that staffers frequently “cry” on set.

Kelly, 47, has tried to reposition herself as a warm, Oprah-like figure, dancing with “Today” colleague Hoda Kotb on-air and peppering her show with cooking segments and weight-loss experts. But the tenacity and combativeness that made Kelly Fox’s prized anchor may spell her doom at NBC, where, sources say, she is viewed as unrelatable for morning viewership.

On the first episode of “Megyn Kelly Today,” the news personality, who had worked at Fox for 13 years, proclaimed that she was “kinda done with politics.”

Not everyone is buying the transformation. “You take someone who had a show . . . on Fox about politics and then you say, ‘Well, that wasn’t really me.’ That’s ridiculous,” said TV producer Shelley Ross.

According to the high-ranking NBC veteran, network execs and talent question Kelly’s longevity at the Peacock Network.

“She is hated inside the ‘Today’ show and is seen as tarnishing the brand, out of control and selfish,” said the NBC source, explaining that celebrity interviews are a key element of “Today” — and Kelly is playing with fire by attacking guests such as Fonda.

According to a show contributor, producers avoid using Kelly’s name when booking guests, opting to just say “Today” with the hope of not alienating big-wattage stars.

In the show’s first week, Kelly enraged two megacelebs. Debra Messing publicly expressed regret for appearing on the program after Kelly asked a “Will & Grace” fan whether it was “true that you became a lawyer — and you became gay — because of Will?” Then Kelly pointedly asked Fonda about her plastic surgery, leading the actress to balk and later complain that it was “weird.”

But it was months later — after Fonda had poked fun at the incident during a “Today” interview with Kotb and Savannah Guthrie — that Kelly retaliated, dredging up Fonda’s decades-old participation in Vietnam War protests. “Honestly, she has no business lecturing anyone on what qualifies as offensive,” Kelly proclaimed on-air. She added that Fonda’s “plastic surgery is tough to ignore.”

One celebrity publicist said Kelly is tainted among the Hollywood crowd. “She’s a little rough around the edges for the ‘Today’ show,’” said the flack. “It’s my job to be smart and plan and I don’t think she’s a smart move. I won’t even let my NBC talent go on her show. She’s a loose cannon.”

Despite NBC shelling out $23 million annually for Kelly’s three-year contract, the network source said that “the general feeling is that she will not last three years.” (NBC declined to comment for this story.)

The show contributor said, “The atmosphere is really negative . . . [producers] just want to get through this.”

Kelly wasn’t always destined for controversy.

Born in Champaign, Ill., to a professor father and a mother who was a nurse, she studied political science at Syracuse University before graduating from Albany Law School in 1995. Kelly worked as a lawyer in Chicago until 2003, when she decided to give journalism a go and moved to Washington. She was hired by an ABC affiliate as a general assignment reporter and joined the Fox News team in New York City in 2004, contributing legal segments during “Weekend Live.” At the time, Kelly was married to Daniel Kendall, an anesthesiologist. In 2006, the pair split, because, as Kendall told the Daily Mail in 2015: “I wanted a wife and she wanted a wife — we both needed someone to cook and clean and support us.”

In 2008, Kelly married cybersecurity CEO-turned-novelist Douglas Brunt, with whom she has three young children.

By 2010, she landed an afternoon show, “America Live,” then was promoted to prime time in 2013 with “The Kelly File,” becoming Fox’s second-most highly rated anchor. When Donald Trump attacked Kelly during a 2015 presidential debate, stating that you could “see there was blood coming out of her eyes, blood coming out of her wherever,” Kelly defended herself gloriously — and became a feminist icon.

NBC wanted in.

With her Fox contract up in 2017, NBC began courting Kelly in 2016, finally landing the star in January 2017 for a rumored $23 million-a-year contract, $2 million shy of former “Today” anchor Matt Lauer’s paycheck. She also makes more than current “Today” lead anchors Kotb and Guthrie combined.

Several insiders blame NBC for fumbling the ball with Kelly’s career by not giving her the best showcase for her skills.

“When [Andy Lack, chairman of NBCUniversal News Group] hired Megyn, he told people, ‘I have no idea what she’ll do, but I’ve got her,’ ” said the NBC veteran. (A source close to the show said that this is a “nonsensical claim” and that Lack always had a plan.)

It was eventually confirmed that Kelly would take over the third hour of “Today.” Before her debut, NBC introduced her to viewers with an evening newsmagazine show, “Sunday Night With Megyn Kelly,” which aired this past June.

Kelly immediately came under fire for interviewing conspiracy theorist Alex Jones, who claimed the Sandy Hook Elementary School shooting massacre never happened.

“She pissed off the audience she needed to be watching ‘Megyn Kelly Today,’ ” said one media insider. “How do you not properly position her going into the ‘Today’ show? You want her to have . . . the most positive image possible, and what do they do? They do the exact opposite.”

The Sunday night show, which bombed, finishing third behind CBS’s “60 Minutes” and ABC’s “America’s Funniest Home Videos” reruns, was supposed to run for 10 episodes but was ultimately cut down to eight. Despite promises of a spring 2018 return, the media insider said the show’s been killed.

TV producer Ross said that Kelly was a “miscalculation” by management, noting she’s “the wrong personality for a morning audience.

“I was the executive who brought Diane Sawyer into ‘Good Morning America’ [in 1999] . . . She had a very distant relationship with the audience — there wasn’t a bond,” said Ross. She recalled assigning Sawyer a story set in an overnight sleep lab so that people could see the cool blonde sans makeup and find out “who she was outside of that anchor chair,” said Ross.

While Kotb and Guthrie hit tough topics with an emotional touch, Kelly doesn’t adhere to the unspoken protocol of gentle morning television. Once, during a January episode, she announced that she used to ask her stepfather to call her a “fat ass” whenever she went to the kitchen during law school.

Ross said that Kelly “popped” at Fox, “but . . . morning news is about talking to people, not just talking at them. It’s not about monologues.”

The contributor said that Kelly lacks the natural rapport of other “Today” hosts. She recalled the time when Kelly turned combative after she teased the host on-air for questioning a tip: “I felt it. Megyn immediately became nasty.

“There are some rules when you’re doing segments,” added the contributor. “If you’re a host, you go along with whatever the expert says. If you eat something and you don’t like it, you don’t say you don’t like it. If you think a tip is dumb, you don’t say it. But Megyn doesn’t play along. She rolls her eyes a lot and says, ‘Oh, come on!’

“It’s like she’s trying to divorce herself from the cheesiness of morning television.”

The program, which has a live studio audience — a first for Kelly — is scrambling to fill seats, according to the NBC veteran, who said cameramen have to shoot around empty spots. The source close to “Today” disagreed, claiming, “The show has been selling out for weeks and we’ve been turning people away.” But as of Friday, only one show was sold out through the end of March via its online ticket service.

While “Megyn Kelly Today” is up 18 percent in the 25-to-54 demographic since its launch, ratings still aren’t where the network wants them to be and it’s affecting the 10 a.m. viewership. According to Nielsen, Kotb and Kathie Lee Gifford’s ratings have dropped 20 percent since Kelly’s show first aired.

Meanwhile, the NBC veteran said that opting not to have Kelly join the other “Today” anchors at the Olympics “was a sign that [producers] were creating a wall between her and the rest of ‘Today.’ You can feel Andy [Lack] and [NBC News president] Noah [Oppenheim] stepping away from her.”

But the source close to the show said, “They are pleased and proud of what she’s done so far.”

As the publicist put it, now is the time to let Kelly excel at what she does best: hunting down big news stories and giving subjects probing, meaningful interviews — at a time of day when it feels right.

“They need to switch her to specials or investigative reporting,” said the flack. “Anything to get her off the 9 o’clock hour.”