Predict Leia will die at beginning of Episode IX
They will use some footage that she just shot and take it out of XIII and put it in IX...plus body doubles and digital effects...they will use that to create some scenes of her demise. Her ship will probably be destroyed in outer space...and then we'll see the reaction shot of the other characters in order to help feel the pain, loss, etc. We'll see a brief scene of her funeral as well.
So, the only one left of the original crew will be Luke in IX.
In XIII Kylo Ren kills Rey through decapitation and in IX he fights Luke and we find out they plotted this entire thing to take down Snoke in Episode X.