Unpopular opinion here and probably completely wrong:
I'm holding out hope that Evan Peters' addition as Wanda's brother "recast" is just a nod to fans and is not the Quicksilver from the Fox-Men universe. Movies have done these kind of meta things before. Examples would be Danny Glover's appearance in Maverick (for fans of Lethal Weapon) or the cameos of the original Murdock and "Face" in the A-Team remake. Most recently,
[Show spoiler]Linda Carter's
post-credits scene in WW84, albeit in a different role.
I am willing to concede that I'm most likely completely wrong. I am a fan of the Fox-Men movies even X-Men Origins: Wolverine (well, maybe just the first half of that one) but I really do think that the introduction of X-Men/mutants into the MCU should be a fresh start like they did with the MCU/Sony Peter Parker. That is not to say that the multi-verse shouldn't come into play with the introduction. I always kind of assumed they would follow in the footsteps of the big merger of the 616 universe with the Ultimate universe in the comics (minus the IMHO awful BattleWorld stories). In the comics, Ultimate Miles Morales (including some family and friends) became a part of the 616 as if he had always been there. My theory would be the same for the introduction of mutants in the MCU; Merged with another universe that has always had mutants and the soft retcon of some events in the MCU (nothing too big or that would pull any of the previous movies, shows, or shorts out of canon).
Again, I am more than likely completely wrong, but that is how I'd do it if I were part of the decision making team.
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