Another aspect could be that the fanfiction delves into how Kushina's presence affects Naruto's relationships with others. For instance, his relationship with Sasuke could be different. With a strong maternal figure in his life, Naruto might be more stable emotionally and be able to approach Sasuke in a more understanding way, which could potentially change the whole dynamic of their rivalry and friendship.
In certain fanfic concepts, Naruto could have found a special relic or artifact. This relic might have the power to reverse death. Since Naruto is always on adventures and exploring different places, he might stumble upon such an item and use it to revive Kushina. It could also be related to the Uzumaki clan's secrets that he uncovers which enables him to bring his mother back.
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.
One possible reason could be for Naruto's protection. Maybe she thought by banishing him from a certain place or situation, she could keep him away from a hidden danger that she knew about. For example, there might be a powerful enemy targeting Naruto specifically, and she believed that by making him leave, he would be harder to find.
Perhaps Naruto finds a way to travel back in time and prevent Kushina's death in the first place. He could use his Sage Mode or some other special ability to manipulate time. And then, by changing the past, he effectively'revives' her in the present. In the Naruto universe, there are all kinds of crazy powers, so time - travel isn't completely out of the question.
In some fanfictions, the authors might take creative liberties and create alternate universes where Naruto and Kushina interact in different scenarios. For example, they could be on a joint mission together, and through that, we see their personalities shine. Kushina's fiery nature and Naruto's determination would make for an interesting dynamic.
One possible fanfic could be about Kushina's early days in the Hidden Leaf. It might explore her training as a ninja, her relationships with her peers, and how she was perceived in the village. Maybe it delves into her friendship with Mikoto and how they supported each other during their pregnancies.
One possible fanfiction could be about Kushina finding Naruto in a situation where he's lost in a forest. Maybe she uses her unique chakra sensing abilities to track him down. It could be a heartwarming story of a mother reuniting with her son.
Well, at first, it might be a bit awkward as they adjust to being husband and wife. But as time passes, they start to understand each other on a deeper level. Kushina could help Naruto deal with his insecurities and Naruto could support Kushina in her goals for the village. They might have small arguments here and there, but overall, their love and respect for each other would grow.
Maybe it's because Naruto has some sort of special connection or resemblance to the Kyuubi that Kushina notices. For example, Naruto might display some of the Kyuubi's power characteristics in an obvious way that makes Kushina jump to that conclusion.