One popular 'Kushina reclaiming Naruto' fanfiction could be 'Kushina's Return'. In this story, Kushina might come back to life and start to make up for the lost time with Naruto. She could use her strong will and Uzumaki powers to protect him from various threats that he still faces in the ninja world.
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.
The antagonist could be Orochimaru. He has always been interested in Naruto's power, especially the Nine - Tails. Maybe he has found a new way to control Naruto and has taken him away from Konoha. Orochimaru's motives would be his never - ending thirst for power and knowledge. He could be using Naruto as a guinea pig for some new and dangerous experiment related to the tailed beasts.
One possible plot could be that Konoha Village has to reclaim Naruto after he has been lost in a mysterious dimension. The villagers might realize his importance more than ever and send out a team of elite ninjas, including Sasuke and Sakura perhaps. They would face numerous challenges in this other dimension, like strange new jutsus and powerful enemies. Along the way, they would also discover new things about Naruto's powers that even he wasn't aware of.
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 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.
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.