Reportedly, Lucasfilm and Episode IX director Colin Trevorrow will meet soon to discuss their options moving forward.
Image: Star Wars: The Force Awakens, Lucasfilm/Disney
According to The Hollywood Reporter's sources, Leia had two key scenes planned out for Episodes VIII and IX, and they're both pretty much what you'd expect (and want): A reunion with her brother, Luke, and a confrontation with her son, Kylo Ren. There's no word on which, if either, of these were scripted for Episode VIII (which Carrie Fisher had finished filming before her death) or were planned for the ninth Saga film.
However, The Hollywood Reporter also claims that Leia was going to have a larger role in the ninth movie than the eighth. That backs up a December 30 report about the amount Disney might get as a result of an insurance policy taken out if Fisher couldn't finish filming on Star Wars. Plus, it seems likely to me that if one of those scenes was in Episode VIII, it would be the brother-sister reunion.
Trevorrow, who is writing and directing Episode IX, is set to meet with Lucasfilm's Kathleen Kennedy next week to talk through what to do. It seems like the options are a) write Leia out, either by death or by some convenience or b) create a CG Leia, like they did for Rogue One. The latter isn't going to be without controversy, since it barely worked for the cameo there and, to many, it still feels wrong to resurrect dead actors this way. The former leaves us with either conveniently putting Leia out of touch with the main storyline or having her die, in-universe. But I have to say, an off-screen death also seems like a poor way for Leia to go out.
There's really no good option here and decisions have to be made by people still grieving.