2) Gambit
Had everything gone according to plan, Gambit would have been released last month. As things currently stand, however, it honestly doesn’t look like the movie is ever going to happen, but one way to generate some excitement for it would be to have Channing Tatum make some sort of cameo appearance in Logan.
The two characters have some history of teaming up on the big screen after Taylor Kitsch played the hero in X-Men Origins: Wolverine, though it’s tough to say whether that increases or decreases the chance of an appearance from the Cajun hero here.
Gambit is also yet another character with links to Mr. Sinister, so that would be one way to incorporate him into this story, but unless Fox is committed to making the spinoff happen, maybe teasing fans with a cameo wouldn’t be the wisest idea.