Obviously, Naruto and Annabeth are main characters. Naruto as the father figure and Annabeth as his daughter. There might also be other characters from the Naruto universe like Sasuke or Kakashi who could be brought into the story to interact with the characters from the Percy Jackson world, like Percy himself or Grover.
Obviously Naruto would be the main character. There might also be some new characters introduced, like the gods that he is related to or other ninjas who are affected by his new status.
Since it's a fanfiction, Naruto is definitely one of the main characters as the title implies he has a father - like role. As for RWBY characters, it could be Ruby Rose. Maybe she is the one Naruto takes under his wing in this story.
Obviously Naruto would be one of the main characters since the title implies his role. And then, there might be characters representing kami and shinigami. There could also be Naruto's friends like Sasuke, Sakura, etc. who would be involved in the story and react to Naruto's new status.
Obviously Naruto would be one of the main characters since it's in his name. There might also be some clone characters that he has a special relationship with, like a first - created clone that he treats like a son or something.
In addition to Naruto and Anakin, the fanfiction might introduce some Naruto - universe characters into the Star Wars setting. For example, Sasuke could show up. His rivalry with Naruto could translate into some sort of conflict or cooperation in the new universe. And of course, the Sith Lords would be there as the antagonists. They would be interested in Anakin's potential, and Naruto would have to protect his son from their influence.
Naruto is surely the central figure in this fanfiction as it's about his role as the father of the Kyuubi. The Kyuubi is essential as well. Additionally, characters like Jiraiya might be included. Jiraiya could play a role in guiding Naruto in this new aspect of his life, considering his relationship with Naruto in the original series. Other characters such as the Hokages could also be involved, maybe to give their perspective on this extraordinary situation.
The main characters are Annabeth and Jackson, but depending on the plot of the fanfiction, new characters might be introduced. These could be original characters created by the fanfiction writer, perhaps a mysterious mentor figure who guides Annabeth and Jackson on their journey, or a villain who is specifically after them for some reason.
It could also be someone new, a character created specifically for the fanfiction. Maybe a powerful new demigod who catches Annabeth's eye, and their relationship leads to the pregnancy.
Well, aside from Naruto and Minato, there could also be other characters like Kushina, Naruto's mother. Since it's about family similarities, she might play a role in showing how Naruto has traits from both his parents. Also, characters like Jiraiya could be involved as he was Minato's teacher and also had a great influence on Naruto.
A mentor - like figure could also be a main character. This could be an older student or a teacher who takes Annabeth under their wing. They could offer her advice, help her understand the unwritten rules of the new place, and guide her through difficult situations. For instance, if Annabeth is in a new school with a complex social hierarchy, this mentor could help her find her place within it.