Yoda spin-off movie. Fully set on Dagobah, have it play out like Predator, only instead of Arnold, it's Yoda, instead of a human supporting cast, get a creature supported cast. Instead of a Predator, you have droves of Imperial forces attempting to seek and destroy Yoda. Darth Vader spin-off movie. Set on various planets where Jedi have fled from Order 66. Vader hunts down Jedi by using the maps of all Jedi temples (minus one because of Luke Skywalker). This could be in a Slender Man video game style (dark figure in the woods haunting you, similar to how Kylo Ren presents himself to Rey before he asks her where the droid is and then knocking her out). Of course, different planets, different settings, so you could use a lot of horror imagery, much like the Darth Vader hallway scene at the end of Rogue One. I also thought about an Obi-Wan spin-off movie, liberating slaves from outposts of Tusken Raiders, with a similar style to John Carpenter's The Thing. Also combine elements of Tremors (underground sand-worms that can eat you alive). I guess you could also take horror imagery from other horror movies to make it stand out.