Oh, she's almost certainly getting redeemed in some way. Just look at the difference between how she was portrayed in BfA and what they're doing with her now. Blizzard is clearly trying to have people warm up to Sylvanas, which likely means that they're going to try pulling some redemption arc.
The problem with Sylvanas is that she's a very polarizing character. Lots of people hate her and want her dead. On the other hand, she also has a lot of fans. If Blizzard redeems Sylvanas, the former will be mad, if they kill her off then that latter will riot. Sucks either way. That's why I think they will go for some middle ground option, i.e. Sylvanas will die or get stuck in the Shadowlands, but she'll get to be a hero before that happens.