A woman who struck two people with an axe at a Sydney convenience store sent threatening messages to a woman she met on Tinder just over an hour before the attack, a court has heard.

Evie Amati, 26, is on trial in the NSW District Court accused of the attack at a 7-Eleven store at Enmore in Sydney's inner-west in the early hours of January 7, 2017.

It is alleged the transgender woman strolled into the convenience store at 2:19am with an axe and used it to hit Ben Rimmer in the face and Sharon Hacker in the back of the head.

Mr Rimmer was buying a meat pie, and Ms Hacker was buying milk.

The Crown said Ms Amati then swung the axe at another man after leaving the store.

Evie Amati is accused of attacking people with an axe in a Sydney 7-11 store. ( Supplied: Facebook )

All three people survived.

Ms Amati has pleaded not guilty to the axe attacks because she was mentally ill at the time.

The court heard Ms Amati met up with Mickila Jahnsen, who was 25 at the time, earlier that night.

They had connected on the dating app Tinder and then exchanged messages on Facebook.

Ms Amati went to her house in Marrickville where, in the company of Ms Jahnsen's friends, they drank vodka and each took the drug MDMA in preparation for going out, Ms Jahnsen said.

Ms Jahnsen told the court they were en route to the Burdekin Hotel in Darlinghurst, when Ms Amati "suddenly" stopped the car to get out.

"She seemed kinda mad, angry and I was confused why," Ms Jahnsen said.

Tinder date 'freaked out', 'blocked' Amati

The court heard the pair then exchanged messages which started because Ms Jahnsen said she was concerned for Ms Amati's safety.

The court heard that in the message exchange, Ms Amati said she felt as though Ms Jahnsen thought she was "ugly" and she could tell she was not "attracted" to her.

Ms Jahnsen told the court the messages then escalated and Ms Amati called her a "sociopath" and said "people like you is what's wrong with the world".

"One day I'm going to kill a lot of people and it will be your fault," Ms Jahnsen said was in one of the messages.

"I freaked out and blocked her on Facebook," Ms Jahnsen told the court.

The last messages were sent an hour before the alleged attack.

Ms Amati shook her head in disagreement during parts of Ms Jahnsen's evidence.

The trial continues.