In some fanfictions, Naruto might be manipulated by an evil force like Obito was by Madara. Maybe a powerful enemy tricks Naruto into believing that the only way to achieve true peace is through extreme means, causing him to abandon his original ideals and start acting more like Obito.
One way could be that Naruto experiences a great loss, similar to Obito losing Rin. This loss could make him question the ninja world and its values, leading him to take a darker path. For example, if he lost Hinata in a cruel way, it might shatter his positive view of the world.
Another plot could be that Naruto is tricked into believing a false narrative about the ninja world. Similar to how Obito was manipulated by Madara's lies. He then starts to act in ways that are contrary to his usual self. He might target the other villages, thinking he is doing the right thing for some grand, but misconstrued reason. This would lead to him being at odds with his former friends, who would be desperate to bring the old Naruto back.
Well, it could be for the sake of exploring a darker side of Naruto's character. Writers often like to take a well - known positive character and see what would happen if they were pushed to their limits. Losing someone he loves deeply or being betrayed could be the trigger.
One possible scenario could be that all of Naruto's friends are killed in a great battle. He survives but is left alone, haunted by the memories of his lost comrades. He might then wander the world, a solitary figure, with his only company being the memories of the past.
Maybe in the fanfiction, Obito makes a deal with an enemy that Naruto sees as a betrayal. So Naruto, with his strong sense of loyalty to the village and his friends, decides to abandon Obito. This could lead to a series of events where Obito tries to redeem himself in Naruto's eyes.
One possible plot twist could be that Obito was actually being controlled by a more powerful force all along. When his identity is revealed, it seems like he's the mastermind, but later it's discovered that he was just a puppet. Another twist could be that Obito has a secret alliance with a character that no one expected, like a member of the Leaf Village elders. This alliance was formed for a reason that is only revealed later in the story.
It might be for the greater good. If Obito's actions in the fanfic are leading to destruction on a large scale, Konan, being a protector of sorts, decides to take him out to save the world or at least her part of it.
One way is in their movement. Ezra Scarlet might move gracefully and swiftly. Naruto could be written to do the same, instead of his normal running and jumping. He could glide across the battlefield like Ezra. Another way is in the use of weapons. If Ezra Scarlet uses a particular weapon, Naruto could be given a similar - looking weapon in the fanfiction and use it in a similar style.
One possible reason could be that Obito sees Naruto as a means to fulfill his own twisted ideals. Maybe he wants to shape Naruto into a weapon against the Hidden Leaf. Another reason might be that he feels some sort of connection to Naruto because of their shared experiences of being alone and ostracized in the past. He could also think that by taking Naruto as a baby, he can prevent Naruto from becoming the hero the village wants him to be, thus disrupting the balance in the ninja world.
The similarity between Naruto and Obito is a big draw. They both had difficult pasts and strong desires. Fanfictions that explore how Naruto could be like Obito allow readers to see different sides of Naruto's character. It's interesting to think about how Naruto might react if he had faced the same things as Obito.
If Naruto was raised by Obito, he would likely be more exposed to the Uchiha side of things. Obito could train Naruto to be a more stealthy and strategic fighter. Naruto might not have the same bond with Iruka or the other villagers as in the original. His goals might be more aligned with Obito's views on the ninja world, which could be either for better or for worse. It would definitely make for a very interesting and different Naruto than the one we know.