Okay, checked those items, and now I think the ninja will take it.
Talk skill basically has: Don't Act, Sleep, Death Sentence(39%), Berserk (49%) and CT 0. The first two don't work because of the Grand Helmet, Death Sentence would be a good bet, IF it hits. Berserk can be a double edged sword (literally): On one hand, the Knight won't be able to use Chakra or Accumulate, but if the Knight gets a hit to land, it's likely that it'll be a One Hit KO.
CT 0 (@ 39%) would probably be the biggest asset that the ninja has going for him. His innate speed means it'll be easy to close the gap and make an attempt. If it hits, then it's likely that he can just keep doing it until his double turn, using that to attack. Even if it does not land, the Knight will likely be too far away to physically attack, perhaps a Wave Fist or stat break instead.
For the Knight, all of her Break skills have a decent chance at landing (80-85% for stats, and from 66(weapon)-73% for items). If she can get close and break one of his blood swords, he's kinda fucked. But that's assuming she can get in close.
I would get into the damage/healing ratios of both, but I'm not certain on a couple (huge) things: How much of a boost do you get when using Martial Arts for Punch Art? And, can the innate Protect on Maximillian be dispelled by Refute?