There could also be new characters introduced in the fanfic. Maybe a powerful hermit who takes Naruto under his wing during his banishment and teaches him ancient and powerful ninja techniques that are unknown to Konoha.
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.
Jiraiya could also play a major role. As Naruto's mentor, he might follow Naruto into exile to continue his training or try to convince the Konoha elders to reverse their decision. Kakashi, too, might be conflicted. He has a connection with Naruto and may secretly help him even if it goes against the village's orders.
In the 'naruto banished kills the kyuubi fanfic', Naruto is the central figure. He is the one whose actions drive the story forward. The Kyuubi is another key character. It has a long - standing relationship with Naruto. And even if Naruto kills it, it still has a major impact on the story. Other characters like Kakashi could also be involved. Maybe Kakashi tries to stop Naruto from being banished but fails, and later on has to deal with the consequences of Naruto's actions regarding the Kyuubi.
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.
Another possible main character could be Kakashi. He has a lot of knowledge and experience. In a 'naruto time orb fanfic', he could be the one guiding Naruto or Sasuke in their use of the time orb, or he might even be tempted to use it himself to change some past events that haunt him, like the loss of his comrades.
Obviously Naruto himself is the central character as the story is about him getting disowned. His friends like Sasuke and Sakura might also be involved. Sasuke could be conflicted between his loyalty to the village and his friendship with Naruto. Sakura might initially be confused about whether to side with the village or Naruto. And then there are the village elders like Danzo who could be the ones behind Naruto's disownment in the fanfic.
Obviously Naruto himself is the central character. Sakura might also be involved as she could be one of the few in the village who believes in Naruto's innocence and tries to help him from afar.
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.
Sasuke could definitely be one. He might be conflicted about Naruto's banishment, either thinking Naruto deserved it at first and then changing his mind, or trying to find a way to bring Naruto back. Kakashi could also be in it. He might be one of the few in the village who believe in Naruto's innocence and try to secretly help him.
Sasuke could be involved. He and Naruto often have intertwined stories. Sasuke might either be an ally in Naruto's destruction of Iwa, or he could be there for his own reasons, like seeking power or revenge.
There could also be some new characters created specifically for the fanfic. Maybe a foreign diplomat who comes to Konoha and Naruto is the first one to welcome him and befriend him. This would open up new storylines about international relations in the Naruto world and how Naruto's friendship can have a positive impact on a larger scale.