I don't think any other general would be able to accomplish the same complete one sided decimation that Moubu delivered against Rihaku and Kousonryuu on the field, and that was the vital key that allowed them to push Zhao back into the woods so early on in the war.
I don't think Duke Hyou would be able to rally the peasants the same way that Moubu did, peasants usually fear being put under Duke Hyou because of how reckless he is with their lives, and I don't think he would come up with the same plan to spend the first day getting them up to speed with the rest of his army. I'm doubtful a blind charge would do it for him since if Rihaku snakes around then that's going to prove more effective on Duke whose power is focused entirely in the front then it did on Moubu who is overall destruction that can fight them off from all angles, especially if he hasn't built up his peasants beforehand.
I guess the advantage Duke Hyou has over Moubu there is better communication and relations with Ouki, for instance, I don't think he would have turned down Kanou's help when he made the offer. He's still a much greater general than his opposition and he has Ouki and Tou overseeing the battle who can potentially step in and give a hand if needed, so he'll still do fine. I just think it would be a more lengthy and time consuming process for them and not the unstoppable steamroll that forced a mass Zhao retreat just a four days into the battle. This is assuming Ouki goes with the same exact setup, it's possible he changes things a bit since he's working with a different piece here, but with both Moubu and Duke being the direct offensive types I think it's likely to be more or less the same general layout.
Once they get into the forest is where Duke Hyou will be more beneficial than Bayou Moubu, since he won't be going near that deathtrap and will be keeping closer communications with Ouki. Even on the off chance that Houken shows up and kills Duke, he would no longer be in a position afterwards to even consider fighting Ouki. His instinct could pick up on the hidden Riboku army and we've already seen how that encounter has played out in the manga, wouldn't have been good for Riboku if he didn't have Houken in close proximity. Ultimately I'd go with a Qin victory here. While Moubu dominated the early half of the war, it was his blunder going into the trap that ultimately cost them the war.
The peasants aren't a problem when Duke Hyou has 95 points in leadership.
The peasants are indeed a problem, but Duke Hyou Elites (which are stronger than Ouki's) would cover them to some extent when they got trapped by Rihaku's formations
And those will maybe inspire the peasants to some extent
Duke Hyou would break through Rihaku's weak defenses.
I agree Duke may not have the same effect on the peasants but I am assuming he has his elites here and they should be more than enough to compensate.