‘Star Wars: De-Incest Edition’
Leia is not Luke’s brother- snip out all the pieces of dialogue that say so.
At the top of my head only includes: Some of the stuff Ghost Obi-Wan tells Luke on Dagobah, some of what Luke says to Leia on Endor, and the baby Leia in Episode III (which I know isn’t OT, but still).
None of this would diminish Leia’s role in any of the films and would remove the incest-y details.