Just wanted to add a 'me too' to this.
Using Fedora/KDE/Bottles (also tried via Steam with Proton).
Ascension worked fine for over a year until a couple of weeks ago. Now it hangs (audio playback stutters repeatibly as well) at the moment that it tries to display a character model from the character selection screen. I have to kill the wow client manually.
All of my other private server wow clients continue to work fine, its only Ascensions that no longer works.
I tried clearing the cache from the launcher. I even tried a complete wipe of the game folder (launcher and wow client) and a reinstall, no joy.
There's something about the character graphic models being displayed that causes the client to hang.