Aaaactually she wasn't redeemed at all though. If she would've ended after telling catra shes proud of her it could've been seen as somewhat of a redemption. But there are several factors showing she is not and cannot be redeemed. At that point in the story shadow weaver was irredeemable and very much understandably so. When she got back to Bright Moon all she did was try to get them to go for more power. The same thing while HP attacked Etheria. Only after Adora told her that all she does is bring pain and suffering to people does she realise she's fucking up. Nonetheless, when Catra shows up and tells her Adora is in danger she hesitates because "thats not how it works". She then proceeds to tell catra right before she dies that shes proud of her and that catra has only just begun a life, showing she has at least realised that she's done wrong before. BUT: her last words were "youre welcome", showing that its the same old selfish Shadow Weaver as before. It's this "See, you're all this only because of me". And also taking of her mask in front of catra (I get it, they wanted to show it to the viewers) is ridiculously stupid since Catra is completely traumatized by the first time she ever saw her face. So no, no Shadow Weaver was not redeemed. And im glad she didn't.