It looks like Tim Miller, the man who directed Deadpool, is currently developing another X-Men project for Fox. This time, he's tackling fan-favorite character Kitty Pryde and developing a solo movie for her. At the present time, it's unclear how far along this movie is in the development stage, but the report does caution that there's no guarantee this movie will ever see the light of day, for various reasons.
With the caveat out of the way that this Kitty Pryde movie is merely being developed and not definitely going to be filming, Tim Miller is said to be "hard at work" on the project. It also isn't clear if he's writing the movie himself, or if he's just developing the idea and will bring on a writer later on in the process. It is being reported that, if all goes well and this movie makes it far enough to actually be given the official green light by Fox, Miller hopes to direct it.
Deadpool is a very different type of character than Kitty Pryde, but considering how great Tim Miller did with that movie, X-Men fans will likely be happy to hear that he's dipping his toes into that universe again. Though, there are many things to consider. For one, there's the Disney/Fox merger. While it can take 12 to 18 months for regulatory bodies to approve the merger, if it's approved, that's something to consider. If and when it becomes approved, Disney will have the rights to the X-Men and Fantastic Four franchises again, meaning that they will control what projects move forward. In the meantime, Fox is operating like it always has and is developing projects as they see fit.
Kitty Pryde has appeared in the X-Men movie franchise previously, with brief cameos in X-Men and X2. Ellen Page played the character, also known as Shadowcat, in X-Men: The Last Stand and X-Men: Days of Future Past. Kitty Pryde first debuted in X-Men #129 and has gone on to become a truly beloved character by fans. She is a mutant who has the ability to become intangible and "phase" her body through any solid material. She can also phase with anyone who happens to be touching her. She can also disrupt electromagnetic fields and has the ability to levitate.
There's no word on what the story for this Kitty Pryde movie will look like. There's a lot to pull from in the world of Marvel Comics. She even took up the mantle of Star-Lord at one point. So there's that if the Disney deal goes through. As for Tim Miller, he's busy producing the Sonic the Hedgehog movie and gearing up to direct Terminator 6, which is set for release next summer. So it's likely he wouldn't really have time to devote to Kitty Pryde, as a director}, until after that movie is done. Collider notes that this is expected to be a solo movie, but it's possible we could see her teaming up with other mutants, depending on what shape the movie ultimately takes.