Well, it could be about Naruto being influenced by some dark force. Maybe he gets tired of the village's treatment and decides to go against it. He might use his powerful jutsu in a more menacing way than before.
Another possibility is Madara Uchiha. Even if he is not fully alive in the original story, in this fanfiction, his spirit or some form of his influence could be present. He could manipulate Naruto's new evil state for his own ends, like trying to destroy the ninja world that he once had a vendetta against.
Well, one possibility is that Naruto could be betrayed by the Hidden Leaf Village. Maybe false accusations are made against him, and in his anger and disappointment, he decides to go rogue. He might then start to form his own group of outcasts who also feel wronged by the ninja system.
The Hidden Leaf Village itself could be the main antagonist. If they turn on Naruto for no good reason, they become the force he has to fight against as a rogue ninja.
Kakashi might also side with Naruto in this scenario. He has trained Naruto and has a deep bond with him. If Kakashi discovers that Naruto has been wronged, he could choose to follow Naruto rather than the village's orders. Additionally, Hinata might be an ally. Her love for Naruto could make her stand by his side, believing in his good nature no matter what the village says.
In a 'naruto goes rogue' fanfic, the plot could involve Naruto feeling betrayed by the Hidden Leaf Village. Maybe he discovers some dark secrets about the village leaders. For example, he might find out they were using him all along. So, he decides to break away and form his own group of outcasts who also felt wronged by the village.
One possible plot could be Naruto feeling betrayed by the village. Maybe he discovers some dark secrets about the Hidden Leaf that make him question his loyalty. For example, if he finds out that the village leaders were involved in unethical experiments. So, instead of following the village's rules blindly, he goes rogue to seek his own version of justice.
It could be the village elders. In the original series, they often made decisions behind the scenes. In a 'naruto goes rogue' scenario, they might be the ones who push Naruto to the edge. For instance, they could be plotting against him to maintain their power in the village.
Perhaps Naruto gets influenced by a dark and ancient power. He starts to see the ninja world as corrupt and decides to reshape it according to his own dark vision. He could form his own army of outcasts and fight against the established ninja villages.