Sasuke could be involved too. He and Naruto have a complex relationship. In the time travel scenario, Sasuke might be initially suspicious of Naruto and Kushina's sudden appearance. But as the story progresses, they could work together to change the future, especially when it comes to issues related to the Uchiha and the overall balance of power in the ninja world.
Jiraiya could also be one of the main characters. He was Naruto's mentor and had a connection with Kushina's family. He could play a role in helping them adjust to the time travel and also use their knowledge to his advantage in some ways, like getting intel on future threats.
In a Naruto and Kushina time travel fanfiction, their relationship dynamics would be fascinating to explore. Kushina could see Naruto as he is now, a powerful ninja, and Naruto would get to experience his mother's presence in a new way. They might team up to train together, with Kushina teaching Naruto some of her unique Uzumaki techniques that were lost over time. This could lead to Naruto becoming even more powerful and having new skills to face his enemies.
Minato could be a common character. Since he was Kushina's husband in the original story, his presence might add some interesting dynamics to the harem scenario. Another could be Jiraiya. His connection to Naruto and his reputation as a bit of a ladies' man could make for an interesting addition to the story.
Obviously, Naruto and Kushina would be the main characters since it's about Naruto being Kushina's brother. But there could also be other important characters. Minato might be a significant character as he was Kushina's husband. Also, characters like Jiraiya could be involved, as he was Naruto's teacher and had a connection to Minato. And then there are Naruto's friends like Sasuke and Sakura, who could interact with Naruto in this new family - centered scenario.
Obviously, Kushina is one of the main characters. Naruto is also a central figure as her son. Since it's related to the Naruto universe, characters like Sasuke, Sakura, Kakashi might also be important in the fanfiction. They could interact with Kushina in various ways, like Sasuke might be skeptical of her at first, or Sakura could be eager to learn from her.
Kushina is a central character as the whole concept is about her remembering things related to Naruto. Naruto, being the subject of her memories, is also a main character. There might also be other characters like Minato, Naruto's father. Since Kushina was married to Minato, he could be part of her memories too. Also, Naruto's friends like Sasuke and Sakura could potentially be in the fanfiction as they are important people in Naruto's life and thus might be part of Kushina's recollections.
Obviously, Kushina herself would be a central character. Minato could also be involved, perhaps in a complex relationship triangle with Naruto and Kushina. Then there are other female ninjas like Tsunade. She might be intrigued by Naruto's time - traveling knowledge and get involved in the story. Sakura could also be a potential character. If she somehow gets dragged into the time travel, she might have her own role in the harem - like situation around Naruto.
Minato might be a common character. Since he is Kushina's husband in the original story, his presence can add an interesting dynamic. Also, Jiraiya could be there. He was Naruto's mentor and his interactions with the harem situation could be quite humorous.
Iruka could be one of the characters. He has always been important to Naruto, and he might try to help Naruto or at least be concerned about his exile. Kakashi could also appear. He has a connection to Naruto and might be conflicted about the situation. And then there are Naruto's friends like Sasuke and Sakura. Sasuke might understand Naruto's feeling of being an outcast more than others, and Sakura could be torn between her loyalty to the village and her friendship with Naruto.
Naruto might be really excited to meet Erza and show off his ninja skills. Kushina could be a bit more cautious, but she'd also be curious. Erza would probably be impressed by Naruto's determination, similar to her own. They could start by sharing stories about their respective worlds, like Naruto talking about his training with Jiraiya and Erza about her time in the Fairy Tail guild. Kushina could chime in with her own experiences in the Hidden Leaf village.
In these fanfictions, the relationship between Naruto and Kushina can be explored in a unique way. Since Naruto has the chance to meet his mother in the past, they could form a strong bond much earlier. It might also affect how Naruto views his own identity, as he gets to know his mother on a deeper level. Maybe he could even learn new jutsu from her that were lost over time.