Yea, and it just broke importing smd files and older saves I had

Blender 4.1 has broken sharp edges, so use 4.0 or below.

Works for source one (Gmod atleast). Have you tried modifing $origin in qc file?

One keyframe is enough

^ Then export everything (you can later delete this animation). I recommend to use proportion trick for any of your custom humanoid armatures if they are about using playermodel native anims

You need to create a keyframe animation for your armature. Press ctrl+tab with your armature selected and press i > Location, Rotation and scale. Hope it helps, it worked for me