There could be some of the more benevolent yokai who see Ichigo as a potential ally. For example, the werewolf Koga might recognize Ichigo's strength and see an opportunity to team up with him against common enemies. Maybe even some of the teachers at the academy who are tired of the chaos and power plays could join forces with Ichigo.
Well, Ichigo might have all kinds of crazy adventures at Yokai Academy. He could use his godlike powers to deal with the various yokai there, maybe make some unlikely friends among the yokai students, or face off against powerful yokai villains.
Yes, in some fanfictions, Ichigo is depicted as the sole male shinigami. This might be because his character is so iconic and central to the original story that writers focus on him as the male shinigami representative in their creative works.
Maybe a mysterious figure from outside the academy's timeline. This person is jealous of the power the academy holds and wants to use Ichigo's time - traveling ability to get inside and destroy it from within, believing that the academy's existence disrupts the balance of the universe.
I hope there isn't such fanfiction. Such content involves non - consensual and inappropriate themes which go against the values of a healthy fictional creation.
Maybe the Shinigami uses its special powers to heal Naruto's severe injuries. For example, it could transfer some of its own spiritual energy to Naruto to revive his fading life force.
Perhaps Ichigo could travel to a future version of the academy that has been taken over by a powerful enemy. He then has to find a way to go back in time and prevent this from happening in the first place. He could also learn new powers in this future academy that he brings back with him to his own time.