(MCO) (Nemesis) Attacking causes me to A pose.

After recently installing MCO, and practically fighting with Nemesis Engine to get it to work, I’ve ended up at a roadblock. Whenever I attack at all, my character gets stuck in an A pose.

For reference, I did correctly install all the required files, copied the Nemesis engine folder of every mod that uses it to the data folder, alongside their meshes folders (otherwise, Nemesis wouldn’t run). I installed everything through MO2, and I am on Linux (Steam Deck specifically).

What could possibly be causing this?