Zazie Beetz came out as a fan favorite in Deadpool 2 when she took over the role of Domino, but she was almost part of the main X-Men franchise.
During her appearance at ACE Comic-Con (via ComicBook), Beetz revealed that she had auditioned to play Storm in X-Men: Apocalypse before Alexandra Shipp was cast. When asked which Marvel character she would play (besides Domino), she explains:
"I mean, when I was a kid I remember in terms of characters people would always be like, ‘You should be Storm.' I auditioned for young Storm, actually, and I didn't get it…"
I feel like growing up I always had an association with her… I mean, obviously, because being a young black woman that was the one I associated with. But I think that would have been a little fantasy of mine to do that, and sort of a nostalgic thing for me to try. So yeah, I'd say Storm."
Seeing that a lot of people love her take of Domino in Deadpool 2, I think we're going to be seeing Beetz in superhero films for a while. She has that X-Force movie coming up, and not to mention, she's also been cast in the upcoming Joker film starring Joaquin Phoenix. The guess is that she's playing the Joker's love interest before his transformation.
With Dark Phoenix said to be ending the main X-Men franchise for Fox, a lot of people are hoping that Marvel Studios will do the same thing they did with Spider-Man and give the franchise a more comic-faithful reboot.
That being said, I hope they keep the Deadpool franchise as it is. Ryan Reynolds has worked too hard to bring the character to life, and it would be a shame of Disney didn't realize that.
We don't know when X-Force is going to come out, but Dark Phoenix is set for a release on June 7, 2019.
See Also: Dark Phoenix's Sophie Turner Sceptical Of The X-Men Joining The MCU