Hello! If you're partial to AUs, would you be at all interested in Beautiful Dreamer? We're a small-to-medium (currently at around 30 players, max player cap is 50) AU game with a pretty chill pace and everyone's been consistently backtag friendly so far! We don't have any HSR characters currently, but the setting allows for a lot of prebaked CR and despite being a mahou shoujo game, we've got a pretty good range of ages depending on what you're looking for in terms of CR.

There's an element of depowering just as part of the AU hook but you can build a character's powerset around their canon powers – or even go haring off with something totally different depending on what interests you!