Apparently, Mixamo uses uses Y-Up, -Z forward. And there's no way to change it. If my character does not match that orientation, the auto-rigger doesn't even work. Unfortunately, the game engine i'm working on is Z up, Y front. How can i quickly fix the orientation of the skeleton and all the animations? If i fix the base pose, it's not going to work for all animations. Should i open all animations exported by Mixamo and rotate/freeze transforms on all root bones?