I was convinced Leia would be in IX via footage from the prior films, and honestly, to an extent, I still am. The film’s still early in development, so despite what KK says, the plan is still likely subject to change. If they don’t include her, it’ll just be one more thing to add to my list of changes to make in my edits. Killing Leia offscreen between films like this is just unacceptable, regardless of Fisher’s death.
There really isn’t much they can do unless they make another Rogue One Tarkin. I’d rather have her go between the films and really focus on Poe as the new leader of the Resistance/Rebellion. He can talk about her and stuff. Oh and maybe we get Poe/Connix?
Also Kylo will never get to see his mother again. He will be all alone, and the last Skywalker. Make lemonade out of lemons.