Originally Posted by
Tantalus
Well, the last X-Men team movie under Fox ruling is Dark Phoenix right? I don't think Fox right now has another X-Men movie being produced, and with the Fox and Disney fusion expected to be completed in the first half of 2019, I think it's safe to assume that Dark Phoenix will be the last one, since it doesn't give Marvel and Disney any advantage to produce any X-Men movie Fox was planning to do, after the fusion.
I believe Marvel will handle the X-Men the same way they handled Spider-Man. So, if we consider only the X-Men team movies (forget the Wolverine ones, since they were their own thing), and considering Dark Phoenix is released, we will have 7 X-Men team movies made by Fox, against 5 Spider-Man movies made by Sony. Amazing Spider-Man 2 was released in 2014, and immediately after Marvel was able to put Spider-Man in their movies, they did, featuring him in Civil War (2016). One year later they released Homecoming. So if Spider-Man, who is one single character, only had to wait 2 years after his last "outside" movie to be introduced to the MCU, why would the X-Men, a team that is composed of multiple members, the biggest part of them being left unexplored by Fox, will have to wait more than 3 years to be introduced to the MCU?
Honestly? I think they will simply throw the X-Men in the universe and that's it. Similar to what they did with Spider-Man. No origin story, no tragical classic events (like uncle Ben dying), but exploring different characters, which gives the audience that sense of freshness and novelty.
And that's easy to do, if Avengers 4 really has time traveling, they can simply establish that the time traveling altered their timeline, and now they live in a timeline where the X-Men exist. Put them as an older team, with the O5 being around 30-40 years old, and use Kitty, a character that wasn't explored a lot by the Fox movies, as the newcomer.
The same thing can be applied to the Fantastic Four.