Have Ben live, Leia’s vision of his death changes, they get married, Reylos unite! Everyone wins.
Have Ben live, but slip away into exile to go be a wandering Robin Hood-type who tries to redeem himself by helping the downtrodden across the galaxy because there’s no way he would be accepted with Rey’s Resistance buddies after what he’s done
I believe that the only way to pull it would be to cut him completely from thr Exegol 3rd act, and restructure the scenes order, so the scene of him and Han Solo wpuld appear just before the final Tatooine scene. He just throws the lightsaber and stands there. It d be a nice ending for him, like, bitter sweet. He s brought back to the light, but what next? What can he do now? It would be a nice end for thos character.
Yeah, it’s definitely not a feasible edit, just wishful thinking on my part.