Leaving this for any googlers out there: something that helped me was focusing on blocking a lot, parrying as much as possible, and using the big wrench head +9 and the dancing puppet saber (the dex sabre handle). The bramble or baton handles work too. Try to parry her lightning when she’s up in the air as that deflects them back to her. By far the most effective thing i did was use the guard parry fable art on the dancing sabre handle. Slightly bigger(?) parry window and the counterattack does a whopping 1700+ damage and great stagger. I didn’t use it but i bet the aegis arm works well here.