Preferably he would be attached to a movie analogous to Deadpool or Logan, where continuity isn’t as essential and action, while still important, is placed on the back burner in favor of emphasizing story and character development.
Assuming Marvel or DC manage to entice Aaron Sorkin into coming aboard, it would be ideal if they don’t put him on one of their bigger releases.
Still, since Sorkin doesn’t have any comic book experience, it will certainly be difficult to find something that both appeals to him and fits with his style of writing.
Someone like him would be better suited for one of the quieter, less bombastic blockbusters.