In a fanfiction where Naruto has Tobi's personality, his relationship with the village would also change. Tobi has an air of secrecy and detachment at times. Naruto might start to distance himself from the villagers in a way. He could still protect them, but his methods would be different. He might not be as open with his emotions towards the villagers, and instead keep them guessing about his true intentions. This would create a lot of tension and new storylines within the village.
If Naruto had Tobi's personality, he might become more mysterious. He could start playing pranks on his friends in a more devious way, like Tobi does. His interactions with Sasuke would be really interesting. Instead of being so straightforward, he'd be more likely to toy with Sasuke, which would completely change the dynamic of their relationship.
Well, Naruto might gain some new powers or knowledge from having Tobi sealed. Maybe he could access Tobi's memories and use that information to prevent future threats.
One way is to tie his alternate personality to a hidden power or a unique kekkei genkai. Maybe this hidden part of him has abilities that no one suspects. This can lead to him being a more complex and unpredictable character in the fanfiction. As he discovers and learns to control this aspect of himself, it can drive the plot forward, especially if other characters start to notice the changes in him.
In some fanfictions, Tobi's alternate personality might be related to a hidden past or a connection to a long - lost shinobi clan. This could lead to a whole new backstory for the character and add depth to his motives in the Naruto universe.
Perhaps it could be due to some ancient and forgotten jutsu that was cast on him unknowingly. There are many powerful and mysterious jutsus in the Naruto universe. Maybe during one of his adventures or even in his early childhood, a jutsu was activated that messed with his mind and created this second personality. It could also be related to his Uzumaki heritage. The Uzumaki clan had many secrets, and maybe this second personality is a manifestation of some latent genetic trait that was triggered by certain events in Naruto's life.
In this fanfiction, Naruto might grow all kinds of unique plants in his garden. Maybe he uses his ninja skills to take care of the plants in an extraordinary way, like using shadow clones to water all the plants at once.
His goal of becoming Hokage might take a different turn. Instead of being the hero that everyone looks up to, he could be a more shadowy figure. He might use his influence as Hokage in a more manipulative way, like Tobi uses his power. So his idea of what it means to be Hokage could be completely warped.
Well, Naruto could use Loki's power of illusion in really interesting ways. He might be able to create false landscapes to mislead his enemies during battles. For example, he could make it seem like there are a thousand clones when there are only a few real ones. This would give him an edge in combat as his opponents would be confused and waste their energy attacking the illusions.
Well, Naruto could become a more stealthy fighter. With Rogue's powers, he might be able to absorb the chakra or abilities of his opponents, which would give him a huge advantage in battles. He could also use Rogue's power - related to stealth and misdirection - to infiltrate enemy bases more easily.
Maybe he's on a secret mission. He could be trying to infiltrate an enemy group that Tobi was associated with. By acting like Tobi, he hopes to gain their trust and gather information.
In such a fanfiction, Naruto might start to reshape the ninja world entirely. He could create new jutsus that are unimaginable with normal power limits. He could also travel to different dimensions effortlessly to learn more about the secrets of chakra and ninjutsu, and then bring back that knowledge to improve the lives of everyone in his own world.