Well, one possibility could be that Kushina takes Naruto away to protect him from the dangerous world of shinobi. Maybe she wants to raise him in a peaceful place away from the constant threats and battles in the Hidden Leaf Village.
One possible consequence could be that Naruto grows up away from the influence of Konoha's shinobi culture. He might develop a different set of values and skills. For example, without the guidance of Iruka and Kakashi, his understanding of ninjutsu and teamwork could be very different. Also, his relationships with characters like Sasuke and Sakura would be greatly affected. Maybe he wouldn't have the same rivalry with Sasuke, and his bond with Sakura might not even form.
One possibility is that Minato takes Naruto away to a secret training ground. There, he could start to teach Naruto advanced jutsu that he never got to pass on before. This would be a way for Minato to make up for lost time and help Naruto become even stronger.
One possible plot could be that Kushina, using her unique abilities or knowledge, helps Naruto gain an edge in his training. Maybe she imparts some secret jutsu or gives him advice on how to better control his chakra, which he then uses to overcome a powerful enemy.
There might also be other characters involved. For example, Minato might make an appearance in flashbacks. Since he was Kushina's husband and Naruto's father, his presence could be important in terms of the backstory. Also, characters from the Hidden Leaf Village might be mentioned or even try to find Naruto and Kushina, like Iruka Sensei who has a special bond with Naruto.
Naruto might discover new Uzumaki techniques. Since the Uzumaki clan was known for their strong sealing jutsu, he could learn some advanced sealing techniques during his visit to Whirlpool. Maybe he'd find a special scroll left by his ancestors that contains a powerful jutsu.
One possible plot could be that they have to face challenges together in a post - war Konoha. They might work on rebuilding the village while also dealing with their new family life. Naruto, with his experience and Kushina's strong will, could make a great team in leading the village in a new direction.
In this fanfiction, the plot might involve Kushina coming back to help Naruto in his toughest battles. Maybe she uses her unique chakra abilities that Naruto has inherited to give him an edge. She could also provide emotional support, as Naruto has always longed for his mother.
One possible plot could be that Naruto somehow inherits the Rinnegan from an unexpected source and Kushina, being his mother, helps him understand and control this new power. Maybe they discover a hidden connection between the Uzumaki clan and the Rinnegan's origin, leading them on a journey to uncover secrets long lost in the ninja world.
One possible plot could be that Naruto, with his powerful jutsu and leadership skills, takes charge in a situation where Kushina's safety is at stake. He might use his Rasengan to fend off enemies and dominate the battlefield, protecting his mother Kushina in the process.
One possible plot could be that Kushina's departure makes Naruto more determined to prove himself. He might strive harder in his ninja training, using the pain of his mother leaving as motivation. This could lead to him achieving new levels of power at a faster rate.