One event could be if Tsunade refuses to help Naruto save one of his friends. Naruto is very loyal to his friends, and if Tsunade stands in the way of him rescuing someone dear to him, it might cause him to hate her. For instance, if she thinks the mission is too dangerous and not worth the risk for the village, but Naruto sees it as a matter of life and death for his friend.
If Tsunade blames Naruto for a big mistake in the village that he didn't actually do. Maybe there is a major security breach in Konoha and she wrongly accuses Naruto of being involved, without proper investigation. Naruto, who has always been trying to protect the village, would be deeply hurt and might start to hate her for not believing in him.
In the fanfic, it could be that Kami has a conflict with one of Naruto's allies, and Kami's actions against that ally make Naruto angry and lead to his hatred. For example, if Kami tries to punish Naruto's friend for no good reason, Naruto would not be happy with Kami at all.
In fanfiction, it could be that the Third Hokage favored certain ninja over Naruto for no good reason. For instance, giving more resources and opportunities to others while Naruto had to struggle on his own. This unfair treatment might be a reason for Naruto's hatred.
Naruto could be developed by having him face moral dilemmas that Tsunade has already experienced. Tsunade can guide him through these, and in the process, Naruto becomes more mature and worldly. Tsunade's character can be developed by Naruto challenging her traditional ways. For example, Naruto might suggest a new approach to handling village finances or medical training, which forces Tsunade to adapt and grow. This interaction would make both characters more three - dimensional in the fanfic.
He might become withdrawn. Instead of being the energetic and outgoing Naruto we know, he could isolate himself from his friends and the village. This would change the whole dynamic of the relationships in the fanfic.
Perhaps the hunters always interfere in Percy's adventures. They might show up at the wrong time and disrupt his plans. For instance, Percy was about to rescue someone, and the hunters came and took over, but in a way that put the person in more danger. This would make Percy resent them. Also, if the hunters have some internal politics that end up affecting Percy negatively, like they accuse him of something he didn't do just to protect their own reputation, that could lead to his hatred.
One possibility is that Hestia took away something important from Percy in the fanfiction. It could be a magical item or a chance to achieve a great goal, which made Percy resent her.
One possible interesting storyline could be Tsunade teaching Naruto some unique medical ninjutsu skills. This would not only expand Naruto's abilities but also create a strong bond between them as mentor and student.
In some fanfics, there could be a misunderstanding. Suppose Kushina did something that Naruto misinterpreted as harmful to him or his friends. This misinterpretation could lead to his hatred. For example, if Kushina was involved in a mission that Naruto thought put the village at risk, but in reality, she had no choice.
One consequence could be that the fanfirls in the fanfic might get sad or angry at being hated. They might stop supporting Naruto in the fan - created stories.
One consequence could be that Naruto leaves the village. He might go on a journey alone, seeking a new purpose away from the place that has caused him so much pain. This would be a major change from his original story where he was so attached to the village.