I was reading the official Marvel press releases of Legion and Hellfire and non of them are very clear about which universe the TV Shows take place in, it could take place in the MCU, XCU or it own universe but none of the press releases stated anything about any movie franchise, could it be that Fox is waiting till Wolverine 3 to announce anything about the TV Shows which are expected to appear in sometime in 2017 possibly after Wolverine 3 which is rumored to be the end of the Bryan Singer X-MEN Franchise:
http://screencrush.com/x-men-apocalypse-wolverine-2-bryan-singer-x-men-universe/
Could it be that Fox either has the option to see how well Spidey does a property co-owned by Marvel and Sony with Sony still having the rights to the character, and probably Marvel isn't getting anymore money then they did when Spidey was outside of the MCU, could it be that Fox is waiting to see how Spidey does and make their decision off of that or have they already made their decision and they are going to introduce the X-MEN in the MCU through the TV Show lets say Hellfire Club deals with the MCU in the 1960s Hank Pym can be named dropped but it deals with why mutants are hidden, and Legion is going to be the reason why the X-MEN are formed in the first place to create a group of people that understand mutant threats better than the ATCU, or SHIELD.
Now I would like to bring up Pete's Basement the guyswho rumored Benedict Cumberbatch for Dr.Strange, the Sony-Spidey deal, they have also rumored a Avengers X-MEN Crossover:http://www.petesbasement.com/MarvelFoxDeal1 and if their track record is anything they do hold a little bit of weight.
Now Marvel has Three unannounced films in Phase 4 all over them are in 2020 could the Avengers X-MEN Crossover be one of the 2020 films, maybe Guardians 3 featuring the Fantastic Four. Marvel has no problem announcing new films why wouldn't they announce their 3 2020 films coming down the pipe could it be that a deal was made that Fox is going to give up the Fantastic Four wholesale after a set period of time, and Marvel and Fox are going to make a deal over the X-MEN after Wolverine 3 allowing Fox to use Iron Man, Cap, and Marvel to use Wolverine, Deadpool, so on and so fourth.
Remember even though the X-MEN TV Shows are being featured on Fox television Marvel still owns the rights that's why it's a co-production.
Why it makes sense for Marvel to do such a thing well, they don't want the X-MEN competing against their universe where they make more money, and why Fox would do such a thing is simple usually a Marvel movie in the same year will do better than a X-MEN film, and alot of Marvel films using lesser known characters have done better than what Fox has done with their A listers, imagine this after a Avengers/X-Men Crossover movie, how much will the next X-MEN movie make, think of it like Iron Man 3, it made a billion dollars after the Avengers outting the X-MEN should do the same if not better, also considering the fact that Ryan Reynolds is not doing any more superhero flicks after Deadpool(google it) , and Hugh Jackman is out of the loop after Wolverine 3 Fox won't have an sure fire way of getting people in the seats, and that character that people go to the X-MEN movies to see, and the X-MEN movie without Wolverine as a prominent character didn't do as well as his own crappy solo movie yes you heard right X-MEN First Class made less than X-MEN Origins Wolverine, and with Marvel and DC on the horizon Fox will have to really fight to stay relevant but the lack of Infinity War level events, or Justice League level events could really dampen that, I mean it's really sad when Ant-Man does better than all your Wolverine movies fox but I digress.
To sum it up, it is possible that Marvel and Fox worked out an Agreement that goes like this, we get the Fantastic Four rights after 2017 because of DVD sales they got to give the people the illusion that their is going to be a sequel so that the one guy who is invested in this franchise can buy it on DVD to enjoy the movie, then Marvel gets the rights back wholesale not just Galactus or Silver Surfer the rights as a whole, I don't think a Sony deal can work for the Fantastic Four because even though Marvel has creative control over Spidey sony is still financing the movie, and I doubt Fox would want to Finance or distrubute the Fantastic Four after this dumpster fire. Fox isn't going to make a sequel nor will their shareholders allow them to make one it will be a waste of money, then after 2017 if Spider-Man does well Fox reboots the X-MEN in the Marvel Cinematic Universe with the Hellfire Club TV Show, and the Legion TV show I mean it would make sense since Hellfire takes place in the late 1960s might as well just reboot with Marvel so you can have the entire Hellfire Club together instead of the few of them, and Legion so he can have his connection to Charles Xavier because it's an important part of his character.