The Disney Fox Merger is what fans have wanted to see for the last decade ever since the Marvel Cinematic Universe began. Marvel has been cashing big money with all the characters that it still had the rights to, and they have turned all the unknown characters into household names. Disney turned the MCU into the biggest franchise in Hollywood even though they did not own the rights to their biggest characters like X-Men, Spider-Man and Fantastic Four.
Now, towards the end of 2017, reports started flowing in that talked about Disney buying Fox. Then Disney announced it officially that they will be buying 20th Century Fox for $52 Billion. That meant that now the rights of big franchises that Fox owned, like X-Men, Fantastic Four, Predator, Avatar and much more will now be owned by Disney. This means that Marvel will now have the rights to bring in X-Men and the Fantastic Four into the MCU.
Still, this deal will not go through till mid-2019, because of the size of the companies, anti-trust regulators must approve all facets of it before the purchase can actually be finalized. This process usually takes more than 2 years, but here it will be done in less, fortunately. Even after the deal goes through fully, there can still be some factors that can reverse it all together.
Also, Kevin Feige, the President of Marvel Studios is not keen to merge the two franchises, MCU and X-Men just yet as X-Men has a lot of baggage and a very convoluted timeline, which will not match with the MCU in any way. As, introducing the X-Men into a Universe would be a big task since here Mutants have never been mentioned before and Inhumans are pretty common.
Well, the X-Men franchise will likely receive a reboot once they show up in the MCU, but that will not happen anytime soon. Even after the deal goes through, the X-Men and the Fantastic Four will still not hit the theatres before 2022, since Marvel is already having plans in mind for the MCU Phase 4 and we will have an upcoming movie slate for movies post Avengers 4.
So the big question that people currently have in mind is that why is 20th century Fox still investing in X-Men movies, when they know that there is no use of them in the near future. Fox currently has so many Marvel related projects under development. Fox currently has at least 7 movies under development and out of those, 3 are have already finished production and are in the post Production stage. The 7 upcoming X-Men projects, for now, are Deadpool 2, X-Men: Dark Phoenix, New Mutants, Gambit, X-Force, Multiple Man, and the untitled Tim Miller Project which is presumed to be a solo Kitty Pryde movie.
The reason why Fox is still making X-Men movies is that until the deal fully goes through and they are completely bought, they have to continue turning their various properties into profits so that they can keep their Investors happy. If the deal does go through successfully and Fox does go to Disney, then all these projects are going to be scrapped immediately, except the Deadpool franchise as Disney would be working to bring these characters into their shared universe which is the very successful and established Marvel Cinematic Universe.
Until the actual merger, it is Business as usual for Fox and X-Men is one of their biggest money making assets, and the Superhero movie business is currently at its peak (and is likely to stay there for the next decade), so they have to continue making money with these properties for the time being. It will serve as the entertainment company we know it as, for the case that it does have a backup already in motion if the humungous deal they are in for does not work their way.
Still, everyone is keen to see this deal go through as soon as possible and finally get to see our dream of seeing the Avengers and the X-Men together. For now, we will have to spend money on the X-Men universe movies as Deadpool will come out on May 18, 2018, X-Men: Dark Phoenix will come out on November 2, 2018, and the New Mutants movie will hit the theatres on February 22, 2019.