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.
Another character that could play a role is Yoda. Yoda's wisdom in the Force could clash or combine with Naruto's ninja wisdom. He might be skeptical of Naruto at first, but as he sees Naruto's positive influence on Anakin, their relationship could develop in an interesting way. And there could be other minor characters from both universes that are added to enrich the story, like Naruto's friends from the Leaf Village or other Jedi in the Star Wars universe.