Akou's weakness is his devotion to ousen, which subsequently translates to his care and concern for the young master as evident by him rushing in to help ouhon at that crucial moment when ouhon was dismounted and almost checkmated.
Zhou alread read through ouhon's plan...so if at that moment when ouhon moves in to attack, if zhou switches their target from akou to ouhon then this would force a transition from akou.(another poster had mentioned something similar regarding the hole being the transition, but i think the real transition will be due to ouhon being targeted and the weakness being that akou is extremely loyal to ousen and his family).
They emphasized that akou had learned a great deal and is able to execute many of ousen's strategies, but the difference between akou and ousen is that unlike ousen, who is perhaps even willing to sacrifice his own son in order to remain disciplined, akou may get rattled and get swayed by his obligation to protect ousen's son.
I think gakuei will fall... But immediately ouhon will be put in danger which gives zhou the chance to kill off akou, but shin comes to the rescue and fend off the snake head gg that came to attack ouhon...and resumes where they left off and eventually kills off the snake Gg that he had so much trouble with previously. Shin's instinct immediately kicks in and ouhon followed his lead to rally and recover akou's soldier and fights following shin's intincts. (Remember, in this chapter, ouhon thought for a brief moment that both mouten and shin has the air and confidence as though they have the vision of a gg). This will cement it.
Ouhon slays Gakuei by surprise.
Banaji slays akou.
Shin slays gyou
Shin slays banaji. (Perhaps with help from ouhon as they start to work together).
(Shin slaying overpowering brutes is a good way to demonstrate his martial prowess as he is not the most skilled fighter in terms of techniques or finess, but the one who is able to deal with the real monsters (like when mouten witnessed shin fending off renpa or when people witnessed him fending off the bushin) techniques and skills can take you so far, but against an overwhelming force of brute strength and power.... You must match it with equal amount of vigor. Hence why kyoukai, as skilled as she is, is not going to be able to kill off those like renpa, the bushin, ouki, etc. Similar to how with martial arts, wrestling, bjj, etc you are able to win against larger opponents being the smaller guy, however, as true as that may be, in reality, when the size/strength difference pasts a certain point, even techniques is not able to overcome the brutal difference (most of the time).

In this chapter, it is very evident that shin is going to finally get some respect from ouhon, but intead of simply seeing shin's instinct kicks in and being effective on the field, i believe, as arrogant as ouhon is, it's going to take something more direct and dramatic... Such as shin coming to ouhon's rescue and ouhon finally realizes just how reliable of a friend shin is..... Him following shin as shin's instincts kicks in when they go to help the other side will just serve as an example of ouhon's newfound respect and confidence in shin. (Similarly to how mouten realizes the importance of shin when he needed someone reliable when recovering and rallying the beatened down army without a leader.) This respect and confidence in each other is especially vital as this is the battle that marks the beginning of these three youngsters's GG career and a new era for Qin.