In a fanfiction scenario, Naruto could save the Uchiha clan by changing the past. Maybe he gets some kind of time - travel jutsu. He could go back in time and prevent the events that led to the Uchiha clan's massacre. For example, he could stop the coup d'état planning by the Uchiha, or he could prevent Itachi from being forced to carry out the massacre. This would completely change the fate of the Uchiha clan.
One way Naruto could save the Uchiha clan in fanfiction is by using his influence. Naruto is highly respected in the village. He could convince the village elders to re - evaluate their treatment of the Uchiha. He might show them that the Uchiha were being wrongly persecuted and that there was a way to co - exist peacefully. He could also use his power as a Jinchuuriki to protect the Uchiha from any external threats that might be a factor in their downfall.
If Naruto saved the Uchiha clan, the story of the Hidden Leaf Village would be rewritten. The history of the Uchiha's massacre would no longer be a dark stain on the village's past. The Uchiha would contribute their unique skills and abilities to the village's development. For example, their Sharingan abilities could be used for better security or in battles against common enemies. There would also be a change in the relationships between characters. People who were once enemies of the Uchiha might have to learn to work with them.
Danzo could be a main antagonist. He was always paranoid about the Uchiha clan's power and was involved in many of the events that led to their downfall. In a fanfiction where Naruto is trying to save the clan, Danzo would likely oppose Naruto's efforts as he sees the Uchiha as a threat to his own power and the village's stability in his own twisted way.
One possible plot could be that Naruto discovers a hidden prophecy about the Uchiha clan's downfall long before it actually happens. He then uses his influence and his own unique abilities to prevent the events that lead to the clan's massacre. For example, he might find a way to resolve the conflict between the Uchiha and the village leadership without bloodshed.
Well, in this fanfiction scenario where Naruto kills the Uchiha clan, it would mean the end of the Sharingan bloodline in a very unexpected way. This would have huge implications for the ninja world. Without the Uchiha, there would be no potential for the Mangekyou Sharingan or the Eternal Mangekyou Sharingan. The balance of power in the ninja world might shift as the Uchiha were quite powerful. And Naruto himself would be a very different character. He's always been about protecting and saving people, so this act would make him a much darker and more complex figure, almost an anti - hero.
A plotline could involve Naruto finding a hidden power within the Uchiha clan that was overlooked. He uses this power to unite the clan and make them strong enough to resist any threats. Maybe this power is related to an ancient Uchiha technique that Naruto helps to rediscover. He then uses his charisma and leadership skills to convince the Uchiha to work with the village instead of against it.
In this fanfiction scenario, Naruto killing the Uchiha clan would make him an outcast in Konoha. The village that once supported him would turn against him. This could lead to Naruto leaving the village and becoming a rogue ninja. He might then form his own group of allies who believe in his cause, whatever that might be in this altered story. It would also change how the Akatsuki views Konoha. Instead of targeting Sasuke, they might target Naruto directly as the one who eliminated the powerful Uchiha clan.
If Naruto was part of the Uchiha clan in fanfiction, it would be really interesting. The Uchiha are known for their powerful Sharingan and their complex family dynamics. Naruto being part of it would mean he'd be involved in all of that. He might have a natural rivalry with other strong Uchiha members. His training would focus more on Uchiha - specific jutsu. Also, his relationship with Kakashi could be different, as Kakashi has his own connection to the Uchiha. The story could explore how Naruto uses his Uzumaki traits in combination with Uchiha abilities to create unique fighting styles and solve the problems in the ninja world.
It could be a situation where Naruto discovers some dark secret about the Uchiha clan that he believes makes them a danger to everyone. For instance, if he found out they were planning a coup that would involve mass destruction, he might think that killing them was the only way to save the village and the rest of the ninja world.
Well, one possibility is that Naruto would be trained in the unique Uchiha techniques. He might learn how to use the Sharingan in ways that no one expected. Also, he could gain a new family within the Uchiha clan, which would change his whole perspective on life and belonging.
In this kind of fanfiction, one possible plot could be that Mikoto is in danger from an unknown enemy. Naruto, with his strong sense of justice and his powerful ninja skills, somehow discovers her plight. Maybe he stumbles upon a battle where Mikoto is outnumbered and on the verge of defeat. He then jumps into the fray, using his Rasengan or other signature moves to fend off the attackers and save her.