Perhaps the Godlike Demon is actually a corrupted form of a good spirit that Naruto has to save. In the process, Naruto discovers a new form of jutsu that combines his own chakra with the purified essence of the demon. This would not only be a cool plot twist but also a great way to expand Naruto's power set.
One interesting plot twist could be that the Godlike Demon character has a hidden connection to Naruto's past. Maybe they are related to an ancient clan that was thought to be extinct. This could change Naruto's understanding of his own heritage and powers.
One interesting plot twist could be Naruto having to adapt to the unique magic system in Highschool DxD. Since Naruto has his chakra-based powers, seeing him struggle or find new ways to use his skills in a world of magic would be cool. For example, he might combine his shadow clone jutsu with some DxD magic to create a new and powerful technique.
One exciting plot twist could be Naruto obtaining the power to use the Dragon Balls in a unique way. Maybe he uses his chakra to unlock a new level of power within the Dragon Balls that no one in the DBZ universe has ever seen. Another could be a fusion between Naruto and Goku, creating a super - powerful being with Naruto's ninja skills and Goku's Saiyan powers. And perhaps there's a plot twist where the villains from both universes team up against the combined might of Naruto and DBZ heroes, forcing them to find new and creative ways to fight back.
One plot twist could be that Dipper, while exploring with Naruto in Gravity Falls, discovers that Naruto's Sharingan (if he had one in this fanfic) is actually a key to unlocking a hidden part of Gravity Falls that no one knew existed. This could lead to a whole new adventure where they have to face new threats and solve new mysteries. Also, a plot twist could be that Mabel befriends a creature in Gravity Falls that has a connection to Naruto's past, revealing a secret about his family.
In a Naruto and Ben 10 crossover fanfiction, an exciting plot twist could be that the DNA of the aliens in Ben's Omnitrix starts to mix with the chakra in Naruto's world. This could result in new forms for both Ben and Naruto. For Naruto, he might gain the ability to transform into a half - alien, half - ninja hybrid with unique powers. Ben, on the other hand, could find that his alien forms now have chakra - based abilities. This would not only change their powers but also how they interact with their respective worlds and enemies.
In a Naruto - Overlord crossover fanfiction, a great plot twist would be if the Ainz Ooal Gown guild members thought that the Sharingan was a powerful and unknown form of magic. They might try to study it or even recruit Sasuke, who has the Sharingan, into their ranks. This would create a complex situation where Sasuke has to decide between his loyalty to Konoha and the allure of the new and powerful world of Overlord.
One interesting plot twist could be the characters swapping their powers. For example, Naruto's shadow clone jutsu being used by a Fairy Tail mage. This would completely change the dynamics of battles in the Fairy Tail world. Another could be a villain from Naruto teaming up with a dark guild in Fairytail, creating a more menacing threat that both universes have to face together. Also, imagine if the nine - tailed fox somehow got involved in the magic - filled world of Fairytail, it would be a huge disruption and lead to some really unexpected story developments.
Well, a great plot twist could be if the Hokage's hat in Naruto's world is somehow connected to a powerful relic in the Castlevania world. Naruto has to journey through the spooky Castlevania realm to find out how to protect the hat and its power from evil forces. Also, imagine if Alucard from Castlevania has a doppelganger in the Naruto world who is a powerful ninja. When they meet, they initially fight but then realize they have a common goal against a greater evil that is threatening both their worlds. And perhaps the Curse Seal in Naruto could be related to the dark magic in Castlevania, causing Naruto to struggle with a new kind of internal darkness that is different from what he's used to.
Often, a plot twist is that Naruto is mistaken for a powerful Pokemon trainer. Due to his godlike abilities, he can easily defeat strong opponents. But then it's revealed that he has no idea about the rules of Pokemon battles. Another plot twist might be that Naruto finds a Pokemon that has powers similar to his own, like a Pokemon that can use a form of Rasengan. This Pokemon then becomes his closest ally in his adventures in the Pokemon world. Also, there could be a twist where Naruto has to use his Sage Mode to save the Pokemon world from a great threat, which no one expected him to be able to do in this new world.
One interesting plot twist could be the discovery that the Philosopher's Stone in the Fullmetal Alchemist world has a connection to the chakra system in Naruto. Maybe it could be used to enhance or disrupt chakra flow in a way that no one expected. Another could be a character from Naruto, like Naruto himself, accidentally using alchemy due to some strange cross - world magic. This would completely change the dynamic as he tries to figure out this new power while still having his ninja abilities.
Another plot twist might be a character swap. For example, imagine if Zuko from the Avatar universe was inserted into the Naruto world. His journey of redemption could be paralleled with that of some of the Naruto characters who have also had to overcome their pasts. In the crossover, he could learn ninjutsu and use his firebending in unique ways, creating a whole new set of challenges and relationships.