The village elders are often depicted as the ones involved in Naruto's betrayal. They might see him as a threat to their power or the stability of the village. Also, some fanfictions might involve Danzo. He has always been a bit of a shadowy figure in the Naruto series, and his underhanded ways could easily be written into a plot where he is behind Naruto's false accusations and subsequent banishment.
Often, Orochimaru could be a character involved in Naruto's betrayal in these fanfictions. Orochimaru has his own motives and thirst for power. He might manipulate events and people within the village to make it seem like Naruto is a danger. He could also plant false evidence against Naruto. And there are those shinobi who are blindly loyal to Orochimaru's ideas. They could be used to carry out the plan to betray and banish Naruto.
In a lot of these fanfictions, Sasuke could be involved in Naruto's betrayal. Maybe Sasuke is lured to the dark side completely and in order to prove his loyalty to a new, evil force, he frames Naruto. It could also be that some of Naruto's former classmates, who are jealous of his progress and popularity, team up with the wrong people and contribute to his downfall and banishment from the village.
Naruto himself could be a victim of family betrayal. His father Minato or mother Kushina might be involved in some alternate - universe plot where they turn against him for some dark reason. Sasuke's family is also a likely candidate. Itachi's actions could be re - imagined in a way where his real motives are more about betrayal of the Uchiha family rather than protecting it. And Hinata's family might be involved too, like if Neji, before his death, was made to betray the Hyuga family in some fan - created scenario.
Well, obviously Naruto himself is the central character. Sasuke could be involved as he has a complex relationship with Naruto. In a crossover, if Naruto is betrayed and ends up in the Dragon Ball universe, Vegeta might be a character he interacts with. Vegeta could initially see Naruto as a weakling but later come to respect his skills. Another character could be Luffy from One Piece. If Naruto is betrayed and crosses over to the One Piece world, Luffy would likely befriend him and help him out, seeing Naruto's situation as similar to his own crewmates' struggles.
Well, Ares could be involved. He has had his clashes with Percy in the original stories. In fanfiction, his war - like nature and desire for chaos could make him set up Percy to look like he's betrayed the community. Also, Octavian from the Roman side might be a character in such a scenario. He's power - hungry and jealous of Percy's status. He could spread false rumors or create situations that make it seem as if Percy has betrayed the Roman demigod community.
Snape is a likely candidate. In the original series, his loyalties were always a bit of a mystery at first. In fanfiction, he could be further explored in terms of false betrayals or real ones. Another one could be Draco Malfoy. He was on the verge of becoming a full - blown Death Eater in the original, so in fanfiction, he could either truly betray his Hogwarts classmates or be wrongly accused of betrayal.
Obviously, Naruto is the central character. But other characters like Sasuke could also be involved. Sasuke might be torn between his loyalty to Konoha and his friendship with Naruto. He could either try to bring Naruto back or join him in his exile.
Captain America could be a likely character to be betrayed. He represents the old - school values of the Avengers, and in a more modern, cynical world within fanfiction, some might see his ideals as outdated and turn against him. Also, Tony Stark. His wealth and sometimes over - confident attitude could make some of the other Avengers, especially those with more humble backgrounds, feel resentful and potentially betray him. And Thor, being an Asgardian, might be betrayed due to the other Avengers' mistrust of his alien nature or the potential threat Asgard could pose.
Sasuke would likely be involved. He has his own issues with Konoha and might side with Naruto, either out of friendship or his own vendetta against the village. Also, the elders of Konoha like Danzo could be important characters as they might be the ones behind Naruto's banishment.
Sakura would likely be involved. She might be one of the first to realize the village made a mistake in banishing Naruto. Kakashi too, as he has always been a mentor figure to Naruto. He could be torn between his loyalty to the village and his belief in Naruto. Sasuke could also play a role. Maybe he hears about Naruto's banishment while on his own journey and decides to help bring him back when he realizes Naruto's importance to the village and to himself.
In some more creative fanfictions, even characters like Kakashi could be made to betray Naruto. Maybe he is put under a powerful genjutsu that makes him see Naruto as an enemy, or he is forced to choose between the village's interests (as misinterpreted by some) and Naruto, and unfortunately chooses the wrong side. However, this would be a more out - of - the - box scenario compared to the more common ones.
Cedric Diggory could be an unexpected character in a betrayal scenario in fanfiction. Maybe in an alternate version, he becomes jealous of Harry's fame from being in the Triwizard Tournament and betrays him. This could be a really interesting twist as Cedric is generally seen as a good and honorable character in the original story.