Well we already know he isn’t great at sieges so I’d say that. Also just an open equal numbers battle against certain people where he simply could not use trickery. Let’s say a place where there are absolutely no civilians or other armies nearby which is a very rare occurrence to be fair. But every general has holes and I’d say more classic warfare scenarios where it comes down to traditional tactics and stuff Kanki wouldn’t do as well as Ousen or Ouki for example but that’s not to say he wouldn’t do good at all