Hey that's crazy, I reported this 3 mins after you without noticing.
Anyway, in my own testing it seems like the transformed mode is fine, it was mainly the one-handed light attack that wasn't working. I'm pretty sure it has a "sweetspot" like halberds in dark souls do, except if you are too close you simply dont hit at all. Unfortunately I overwrote the save I had with blades of mercy so if you want to test more I'd recommend finding which attacks don't hit when u are right beside an enemy