Hara is making Ousen look pretty bad here. Just like others pointed out, he's doing nothing, has prepared nothing which seems a bit out of character for someone who doesn’t pick battles he can't win.
Hara wants us to believe that dude just went there against RBK of all people with nothing under his sleeves after we witnessed Ousen anticipating, planning ahead the whole length of the manga.
And now for one of the most decisive battle for the conquest of Zhao, he has no plan. Weird.
The worst thing is with that view of RBK from far away observing the battle, I had a small vision of Ousen looking at Ordo from above and thinking "what an idiot". Except now he is the idiot in the story.
Kanki looked better with almost 4 times less men vs RBK.