Jillaroos superstar Isabelle Kelly is on the move in 2020 after signing with St George Illawarra for the upcoming NRL Nines in February.

Kelly, who recently married partner Jake Callister, will join a star-studded Dragons outfit for the two-day tournament in Perth, while her long-term future with Sydney Roosters now appears uncertain after two seasons with the club in the Holden Women's Premiership.

The addition of Kelly and inaugural St George Illawarra captain Sam Bremner headlines a strong squad named by the 2019 NRLW runners-up, which includes Golden Boot winner Jessica Sergis and fellow NSW stars Kezie Apps, Maddie Studdon and Shakiah Tungai.

Kelly, Bremner and Illawarra product Kaarla Cowan are the only other members of the 16-player squad who did not feature in St George Illawarra's grand final team.

Bremner, who is returning after missing the entire women's calendar in 2019 following the birth of her first child, Reef, in August, said she was looking forward to playing alongside Kelly – the 2018 Golden Boot winner as the world's best female player.

"Isabelle, myself, Kezie and Maddie have played together a fair bit and we are all really good friends so it is going to be great to have her in our team for the Nines," Bremner said. "Nines is her forte so it is going to be exciting to play with her in Perth."

The Dragons squad had their first training session for the Nines under coach Daniel Lacey last Saturday and Apps said Kelly had immediately fitted in with her new team.

"It's a very big positive for our team, she is a beautiful person and a fantastic athlete so I am very happy that she is at the Dragons," Apps said.

"I feel like the people around her will help to bring the best out in her, hopefully she has fun and it translates into her footy as well.

"I have been speaking a little bit to her about it before she did sign and Lacey has obviously done a really good job so I feel she will be comfortable with the girls that we do have in our team.

"There are a lot of girls in our team who she has played with, we have that connection and that friendship so that has probably helped a little bit for her to come across.

"She had a really good relationship with all the girls at the Roosters too but sometimes a change is good and we'll see how she goes."

Lacey said the signing of Kelly was a coup for the Dragons and he hoped she would now stick with the Red V for this year's NRLW campaign.

"Isabelle was on the top of our list to come to the club for the first NRLW season, and I never gave up hope of her becoming a Dragon one day," Lacey said.

"It speaks volumes for what we're doing as a club for her to want to jump ship and get an insight into how we operate.

"She's only committed to the Nines for now but hopefully we can sit down at some stage and look at her future with the Dragons."

With Kelly and Sergis in the centres, Bremner sharing the fullback role with Botille Davis-Welsh, and Shakiah Tungai, Studdon and Keely Davis also in a potent backline, the Dragons will have plenty of strike power at the NRL Nines.

"We've got quite a good side so it is pretty exciting and it will be fun too," Bremner said. "It is such a great way to start the season so I am excited that this is my first game back. I love the Nines, it is just a bit of fun to start my career off again."

Cowan is the only member of the squad without NRLW experience but she has previously represented the NSW City team at the National Championships as well as the Prime Minister's XiII team in Papua New Guinea.