Hayabusa's does not even need anyone to help him at all. At this point, I don't even want him involved in DOA's story because he will just turn into a joke. (an unfortunate implication of being a godlike individual lore wise)
In NG1, the AI is completely fair. Most of the time, it's your own damn fault if you get hit or die. Master Ninja mode is the only difficulty where it becomes a little cheap.
OG NG2's AI is just stupid.
NG2 had very questionable boss designs however. And no, I am not talking about their AI. Gigadeath, Water Dragon, Nuclear Armadillo, Pterodactyls, etc. There is a reason why the Giant Death Worm got cut out in Sigma 2.
She lacks a lot of tools, and her throws deal only mediocre damage, in addition, her throws are also eratic as hell and usually end up putting herself against the wall. I would really place her at mid tier instead of high tier or low tier.
Why on earth does Hayabusa need so much air throws? Anyway, it seems that his old DOA5 41236T air throw is mapped to just T instead and he can no longer do his 3P+K teleport.