Originally Posted by LokiDionysos
They may not be able to use Kang either because of his relationship with Reed and the FF. I think we might see Annihilus in the new Fantastic Four, however I'm pretty sure they're considering Kang too..
They may be joining X men and Fantastic Four eventually over at Fox with some of the time travel/timeline stuff being planned... Which led to an agreement on Marvel's end, and Fox's over certain characters they were trying to acquire. While Surfer and Galactus remain in their possession, I don't want to say too much at this point but Fox really wants to keep those fantastic four characters in play and separate them from what came before just as much as they're attempting with the x men time travel stuff overcoming the last stand. They'd still control the film rights to certain characters, and they may not have even been willing to just hand over Kang without putting up a challenge.
This means basically we may see Kang in the fantastic four movie(s) talking about how timelines all around the marvel universe have been skewed. FF & X men may be working towards an Age of Apocalypse team up movie after DoFP & the FF reboot.
It's not fox and Marvel working together but coming to an arrangement over certain characters, which would allow both film companies to depict Kang and some of the space characters differently. Clarifying through Kang that they exist in alternate timelines, and alternate film verses, where they're closer to the Age of Apocalyse and Days of Future past future the mutants/FF eventually witness. Instead of the Thanos and Age of Ultron futures the Guardians/Alternate 31st century Guardians, and Avengers witness.
Some of Kang's other forms may be fair game after they tried to get Surfer and Galactus from Fox and this led to an agreement over some characters.
Marvel might not be able to use Kang, but a deal might have been worked out to use another version of Kang & the name Immortus in phase 3 or the post credits to a phase 2 movie. Immortus would have a lot to do with the Guardians, Magus, the 31st century guardians, Thanos, Korvac, and Pym...
The thing about Immortus vs Kang is that Immortus has already traveled time and meditated for many years to become at one with himself. He's been to the dawn of time, knows of the threats coming from that direction in Thor's movies. He's a guardian of this timeline in some ways but he thinks that the Avengers announcing themselves to other worlds has put a certain chain of events in motion. In GoTG he sets up Magus/Korvac against Thanos... He knows Thanos has plans to acquire the gauntlet and this creates the horrible version of the 31st century that the future guardians are from. They contact the past members through knowwhere after they deal with Thanos the first time. Immortus isn't really a bad guy, although he has tried to stop the Avengers from forming throughout the years and his counterpart in the 31st century was a badguy.
Immortus is actually one of the better versions of Kang, he may see the use of timetravel only to alter the events of the final showdown with Thanos because he can't let Thanos destroy half the universe with Gauntlet and ruin the future for the future Guardians, all his selves, and all the influence he's held on preserving the timeline thus far. He realizes his mistake and that Pym is necessary to stop Ultron, save the timeline, and possibly important in defeating Thanos.
In this story his only evil is interfering with Pym's past and being the true reason Pym wasn't there since the beginning and separating him from Wasp, also accidentally created the Age of Ultron by stalling Pym's progress as a hero and making him unsure about becoming a hero + allowing part of Ultron to time-travel to the 31st century... and back again.