X-Force director Drew Goddard confirmed the film will focus on Deadpool, Cable and Domino, a trio of characters he has been a fan of since his childhood.
"It really all stems from a place of love; I love those comics, I love Ryan [Reynolds], I love Josh [Brolin] and I love Zazie Beetz," Goddard told Entertainment Weekly. "When I think of the comics, I think of Cable and Domino and Deadpool, and it’s really just knowing, 'Oh, right, there’s a world in the X-Universe for the blunt instruments of mutantdom.' It’s much more about the characters and my love for them than it is about any plot or storyline. It’s more about loving them and wanting to see them bounce off each other."
"I trust that my love of these three will lead me someplace new,” he added.
Deadpool 2's post-credit scene showed Deadpool traveling back through time to rescue Peter, who joined the first iteration of X-Force, but the Merc With a Mouth made no attempt to save anyone else. That leaves Peter, Domino and Cable as the only ones to walk away from that encounter aside from Deadpool. Per Goddard's comment, it seems Deadpool, Domino and Cable will form the core X-Force team.
Further details about X-Force's script, release date and supporting cast are still pending.