The 20-year-old has featured as a trialist for the Bluebirds in pre-season as the Welsh outfit looks to strengthen their Under-21s side after losing a number of players at the end of last season.
WalesOnline is now reporting that Antwi – who was released by Blackpool at the end of last season – is set to sign permanently for Cardiff with a medical booked in for Thursday.
“They have been with us all week and they have made the training sessions step up to another level,” Cardiff’s Under-21s boss Darren Purse said of the trialists last week.
"They are all a little bit older than what we have got in the squad at the moment, which I think is what we need, a little bit of experience.
"Sometimes the young lads need a bit of experience, a lad that's two or three years older to help them through it and they step up to it when they are up against each other in training.
“It's been good to have them around, they've been very good, and we will see what comes of it in the next couple of weeks."
Antwi came through the youth ranks at Fulham before making the move to Bloomfield Road in 2019.
He made his debut a year later in a 3-0 win against Leeds United in the EFL Trophy. The midfielder’s only other appearance came against Sunderland last season during a 3-2 Carabao Cup defeat.