In a 'naruto meets his counterpart fanfic', a plot twist could be that the counterpart seems friendly at first but is secretly working for an enemy. Or perhaps the counterpart is a clone created by an old enemy of Naruto's with a different set of memories. It could also be that the counterpart has a connection to a long - lost part of Naruto's family that he didn't know about, which changes everything he thought he knew about his own identity.
One possible plotline is that they discover they have a special connection that is related to some ancient ninja prophecy. They then have to go on a journey together to figure out what it means.
One possible plot twist could be that Bowsette turns out to have some sort of connection to Naruto's world that he never expected. Maybe she has a hidden kekkei genkai - like ability that is related to Naruto's ninja powers.
In the 'naruto meets nagato fanfiction', a plot twist might be that Nagato fakes his change of heart at first. He could be playing a long - game to deceive Naruto and the Leaf Village. Or perhaps, there is a prophecy that involves both of them, but it has been misinterpreted all along. And when they meet, they start to uncover the real meaning of the prophecy, which changes everything they thought they knew about their fates and the future of the ninja world.
In such a fanfic, Naruto might initially be confused when he meets his counterpart. They could compare their lives, skills, and experiences. Maybe they would have a friendly spar to test each other's strength.
One possible plot twist could be that Danzo is actually being controlled by an even greater enemy. So, when Naruto is about to defeat him, he realizes that there's a bigger threat behind Danzo. Another could be that Danzo reveals a hidden power that he has been suppressing all along and suddenly becomes much stronger than Naruto expected.
One possible plot twist could be that Naruto discovers a way to nullify Jigen's power. Maybe he finds a weakness in the power source that Jigen draws from. Another twist could be that Jigen is actually being controlled by a greater evil, and Naruto has to figure out a way to free him rather than just defeat him. It could also be that Naruto loses his powers temporarily during the fight and has to rely on his wits and the help of his friends in unexpected ways.
A plot twist could be that Naruto discovers a long - lost connection between the Nine - Tails and some ancient power in Kumo. This could change the whole dynamic of his capture situation. Instead of being a victim, he might become an important figure in Kumo's internal power struggle. And this new - found connection could also lead to a new alliance between Konoha and Kumo in the end. Another twist could be that Naruto's capture was a ruse by Konoha's higher - ups to gain some secret knowledge in Kumo. Naruto was sent there on purpose, but things start to go wrong when Kumo figures out the plan.
One possible plot twist could be that Naruto's closest friend turns out to be secretly working for the enemy. Just when Naruto is about to make a final stand against the invaders, his friend betrays him, leaving him in a difficult situation. But Naruto, being Naruto, manages to find a way to turn the situation around and still save the village.
One possible plot twist could be that Naruto discovers Godzilla is being controlled by an evil force. So instead of just fighting Godzilla, he has to find a way to break the control. Another could be that Godzilla is actually a guardian of some sort, and Naruto misinterprets its actions as aggression at first. Then they end up teaming up against a greater threat.
Maybe the seventh swordsman has a secret power that is unleashed when Naruto is in a dire situation. This power could be something that was thought to be lost or forgotten in the Naruto world, and its appearance changes the entire dynamic of the story.