There are many possibilities. Naruto could be in a situation where he has to rescue some of the other Jinchuuriki. Or perhaps they all gather in a secret place to train and improve their skills. It could also show how Naruto's positive attitude affects the other Jinchuuriki, leading to a change in their outlooks on life and their roles as Jinchuuriki.
In this fanfic, Naruto might gain incredible power. He could have enhanced physical abilities like super strength and speed. His ninjutsu might also reach a whole new level, allowing him to perform feats that were previously impossible.
The important characters would start with Naruto. Then, any of the other Jinchuuriki that the author decides to include. For example, if the story is set in a certain time period, we might see the Jinchuuriki from Naruto's generation more prominently. So, characters like Gaara and Killer Bee would be very important. And there could be some new or less - known Jinchuuriki introduced to add more depth and variety to the story.
In a fanfic where Naruto is the Sanbi Jinchuuriki, he might have different powers. The Sanbi gives abilities related to water and some unique forms of chakra control. Naruto could potentially use these new powers to create more diverse and powerful jutsu. For example, he could combine his already strong wind - style jutsu with water - style jutsu enhanced by the Sanbi's power, making his attacks more unpredictable and deadly.
Perhaps in this fanfic, Naruto would be confused by the concept of the Avatar at first. But as he gets to know more about it, he realizes the similarities between his world and the Avatar world in terms of protecting people. He might also have some interesting interactions with the different tribes in the Avatar world, like the Fire Nation. And who knows, he could even find a way to use chakra to enhance bending abilities.
A 'naruto meets kabuto fanfic' could start with Naruto sensing an unusual chakra signature which turns out to be Kabuto. Naruto would be ready for a fight, but Kabuto might hold up his hands in surrender. They could then have a conversation where Kabuto reveals some secrets about the past, like some hidden experiments of Orochimaru that could still pose a danger. Naruto might then decide to keep Kabuto under watch or try to convince him to use his knowledge for good.
Well, in this fanfic, they could also have an adventure together outside the village. They might encounter a powerful enemy that requires both of their skills to defeat. Naruto's brute strength and Tsunade's precise and powerful attacks could combine to make a great team during the fight. And along the way, they could bond more like a master - student relationship.
In a 'Naruto meets aliens' fanfic, Naruto might use his ninja skills to fight off the aliens. He could use his Shadow Clone Jutsu to confuse them and then strike with his Rasengan.
Well, in such a fanfic, there could be a training session where Minato teaches Naruto some of his signature jutsu. This would be a great opportunity for Naruto to learn more about his family's ninja techniques and heritage. It could also be a chance for Minato to see how strong his son has become.
Well, it could be that Naruto and Nagato initially engage in a fight as they have different ideologies. But then, as they talk more, they might find common ground. Maybe Naruto tells Nagato about his dreams for peace in the ninja world, which makes Nagato re - evaluate his actions. And Nagato could also share his past with Naruto, explaining why he came to his current beliefs.
If Naruto becomes the Juubi Jinchuuriki in fanfiction, it would be a game - changer. He could potentially change the entire ninja world. His influence would be felt everywhere. With such power, he could even reshape the relationships between the different ninja villages. He might also have to deal with the fact that many would fear his new - found power, and he would have to prove that he's still the same Naruto at heart, just with a whole lot more power to protect those he loves.