James McAvoy has talked about whether he'd return to the MCU as Professor X, AKA Charles Xavier.
"I'm all about doing good stuff, and when I got asked to play Charles the first time, it was good stuff," McAvoy told ComicBook.com, when asked if he'd talked to Kevin Feige about returning to Marvel.
"It was good writing, and I was excited. If people offer me good writing, I'm always going to be excited, but I do feel like I've had a good ending with Charles and I got to explore some really good stuff, particularly in the first two movies that I did for him as a character. So if my time is done, I'm happy with the time that I spent and the time that I was given and if good writing comes in and people want to do stuff with me, I'll always be open to that, but it's got to be good."
He added: "If what happens next involves us, then that could be cool, but I'm not sure what way they're going to go with it, basically. But as a fan, I'm excited to see whatever way they go."
With Spider-Man: No Way Home cracking the multiverse wide open, the road has been left clear for Marvel stars to reprise their roles. Alfred Molina will definitely be back in the Spidey threequel, for example, so there's no reason McAvoy could never appear in the MCU as Professor X, despite playing the character in the Fox universe.
Then there's Evan Peters, who reprised his Quicksilver role in WandaVision, though with a twist – the character was revealed to be under the enchantment of Agatha Harkness, and wasn't really Pietro/Peter Maximoff. Deadpool has also been confirmed to be making the jump from Fox to the MCU.