Well then... That went well. Nice chapter by the way.

is she gonna be missing an arm the whole story?

Eh, initial concept was good but the execution is off. The part with the gods was completely unnecessary and felt like the opening to a crack story (which I'm hoping wasn't what you were going for, because ptsd breakdowns don't work with that) and shoehorning in a split personality was just annoying.
Ever heard of the one unicorn rule? Pick a single change (Dragonborn Yang) and go from there. Voices in her head are not part of the standard package and as such should be left out (or at the very least minimized to occasional whispers). Voices that can "assume control" are just pointless oc inserts that completely remove the agency of the protagonist and consequently ruin the story. My recommendation would be to have the dragon hit her with fus ro dah and have that knock her out of her funk, charging her semblance as a side effect.

Nice. DO MORE!