It looks like people holding onto the hope of the First Class era or Singerverse making the jump to the Marvel Cinematic Universe may have finally got their answer. During the Disney presentation at CinemaCon, it was revealed that Dark Phoenix will indeed be the “final chapter”. This would confirm that Deadpool will be the only character, so far, to make the leap to the MCU.
Dark Phoenix is promised as "the perfect sendoff for our X-Men team." It will be the "final chapter" for the X-Men world. #CinemaCon
— Brandon Davis (@BrandonDavisBD) April 3, 2019
It remains to be seen if any of the X-Men cast members will get new Marvel roles, but this does seem to support the idea that Marvel Studios will indeed reboot the X-Men with Deadpool making the jump.
Disney also confirmed that New Mutants will be released in 2019 at the event, which would squash theories the film would be dumped on a streaming platform. I think it’ll be more a question if they’ll make the film a single standalone or add it to the Marvel Cinematic Universe after the fact, similar to Deadpool since those characters are mostly brand new and could have ties to the Singerverse severed.
SOURCE: COMIC BOOK