According the ComicBookMovie, writers of Deadpool, Paul Wernick and Rhett Reese, said they only chose Negasonic Teenage Warhead to be Colossus’ companion because of her name, but the character brought up many complications when filming. Even though the rights of this character belong to 20th Century Fox, they wanted to change her powers (in the comic books, she’s a psychic), and thus had to ask Marvel Studios at Disney, to do so.
Kevin Feige, at Marvel, used this as leverage to make a super hero switch: Negasonic Teenage Warhead’s powers for 20th Century Fox’s Ego the Living Planet. Ego, who will be portrayed by Kurt Russell, will play a main part in James Gunn’s Guardians of the Galaxy Vol. 2. Ego is an alien Kree that first appeared in Thor issue #132 in 1966.
Be on the look out for this swap when Guardians of the Galaxy Vol. 2 hits theaters, May 5, 2017.