Marvel Studios may have built a massively successful shared movie universe off the backs off relatively unknown characters, but Disney's acquisition of Fox could finally bring the X-Men to the MCU. The most well known Marvel characters have always been Spider-Man and several members of the X-Men, but when they were acquired by Disney, Marvel Studios had sold off the rights to most of their most recognizable faces, only ones that were far less popular with mainstream audiences. Nevertheless, Phase 1 of the Marvel Cinematic Universe hit the ground running.
When the Avengers finally hit the big screen in 2012, it wasn't only impressive because it was the first big team-up of its nature, but also because it was done with characters many saw as Marvel's B-squad. While the X-Men and Spider-Man both had a number of big hits, a few critical failures (and the repeated false starts of the Fantastic Four) have always had fans begging for their return to Marvel, confident the perennially successful MCU would provide the best live-action versions of these characters yet.
Spider-Man: Homecoming served as proof that this was the case. Marvel Studios reached a deal with Sony allowing for Spidey's inclusion in the MCU, and while the movie's financial performance didn't hit the same highs as the Sam Raimi movies, general consensus is that Tom Holland's younger Peter Parker is the most comic accurate seen on screen yet, with his inclusion in movies like Civil War or Infinity War simply serving as a cherry on top.
The success of Spider-Man's MCU reboot renewed cries for Marvel Studios to get back the rights for the X-Men (and Fantastic Four), which is now going to officially happen when Disney acquires 20th Century Fox. Needless to say, fans are excited to see the mutants, both old and new, and Marvel's First Family in the MCU, looking around every corner for a surprise introduction; however, acquisitions are not simple things, and fans might be waiting for these characters to appear on screen together for longer than some seem to think.
This Page: Don't Expect a Surprise Introduction of the X-Men
Don't Expect a Surprise Introduction of the X-Men
The second news of the talks between Disney and 20th Century Fox broke, fans immediately jumped to speculate about how the X-Men could ultimately arrive. Time travel? Dimensional hopping? A total reboot of one or both universe after Infinity War and Dark Phoenix? Ever since the ending of Iron Man when Nick Fury appears in a post-credits scene to talk about the Avengers initiative, and even more so since the ending of The Avengers when fans first saw Thanos's giant smile, the idea of major surprise reveals has always been front of mind when it comes to new characters entering the MCU, but unfortunately that's not how the MCU works anymore.
The popularity of the franchise has led to much greater scrutiny on each movie's production, meaning this doesn't happen like it used to. If we knew as much about Marvel's future plans as we do now, there's no way things like Thanos or Fury would have been surprises, and big time cameos are often spoiled ahead of time by casting news or set photos. So it's doubtful that the X-Men will have any sort of surprise introduction, it will likely be something that sees a big announcement and reasonable fanfare like Spider-Man in Civil War.
Recent news of both Dark Phoenix and New Mutants getting pushed back for massive reshoots has led to even more speculation: could this be to add MCU connective tissue? While the options for their eventual inclusion are nearly endless, the one thing that's clear is that it won't be for a few years. Marvel Studios doesn't actually own the rights to the X-Men or Fantastic Four yet, and because of the complications of corporate mergers, they're likely going to be hands-off entirely until the deal is finalized.
Nevertheless, X-Men and F4 have people excited. Marvel just brought in Spider-Man, and there was a fairly quick turnaround, but that’s a different situation. Bringing the X-Men in is far less straightforward and won't happen nearly as quickly.