Vader was only really redeemed in the eyes of Luke, and apparently the Force. I imagine he’d have had a very awkward time trying to ghostsplain to Leia why he made her watch as Tarkin obliterated her entire home planet and everyone she’d ever loved. Or maybe after the Endor Celebration, Anakin never manifested again - from then on he just ghosted his kids 😉
Edit: I wonder if this will be tackled at all by the rumoured post-Rebels Filoni animated show. It’s Filoni, so obviously Ahsoka will be in it, and it doesn’t seem unreasonable that she’d interact with redeemed ghost-Anakin. (Despite not technically being a Jedi, she is a powerful force user, and we hear her voice in TROS so clearly she goes on to learn something about manifesting after death, the Netherworld and all that.) It’d be extremely hard to write though, which is why I don’t think it’s ever been covered significantly in any other Star Wars media.