There’s a really cool fan film that does something like this with the mirror scene in TLJ where instead of seeing herself she sees Jaina Solo and they “talk”.

Imagine a scene where the team goes to the Death Star and sees flashes of their Eu counterparts. Rey sees Jaina and the struggles she had to go through of killing her brother.

An almost “this is what could have been, but the force interfered with the flow of time. Creating you, Rey. The entity was unable to stop Jacen from falling, yet his name did change.”

I don’t know it would be cool
Like how old TMNT crosses over with the one from 2003