Often, there's a theme of discovery. Maybe Naruto Uchiha discovers something special about Kushina Uzumaki that draws him to her, like her strong will or her unique Uzumaki abilities. And also, redemption can be a theme. If Naruto Uchiha has a troubled past, Kushina's love could be the thing that redeems him. There's also the theme of family, as Kushina is Naruto's mother in the original story, so in these fanfictions, they might create a new family dynamic with their relationship.
Yes, there are quite a few. You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'Naruto Uchiha and Kushina Uzumaki love' in their search bars, and you'll find various stories exploring different aspects of their relationship, from sweet and innocent crushes to more complex emotional bonds.
One idea could be a time - travel fanfiction. Naruto Uchiha (assuming it's an AU where Naruto has Uchiha heritage) somehow travels back in time and meets Kushina Uzumaki. They could form an unexpected friendship as he tries to protect her from the events that would lead to her death. He could also use his knowledge of the future to change things in the village for the better.
One of the main themes is love. Not just the mother - son love between Naruto and Kushina, but also how Kushina's love for Naruto can be a driving force in the story. For instance, in some fanfics, Kushina's love gives Naruto the strength to overcome great challenges. Also, the theme of sacrifice is common. Kushina sacrificed herself for Naruto, and fanfics often expand on this idea, showing how Naruto honors her sacrifice and what it means for his character development. In addition, there's often a theme of discovery, where Naruto discovers more about his mother and his own identity as an Uzumaki.
One common theme is the exploration of an alternate relationship. Since they don't have a canonical relationship in the original series, fanfictions often create a new dynamic between them.
Relationships are often a theme. In a Kushina Uzumaki crossover with the Inuyasha world, she might form new friendships or rivalries. Another common theme is the struggle for survival. If she's in a world full of demons or zombies, she has to use her skills to stay alive. Also, the theme of discovery is prevalent. Discovering new places, new forms of magic or technology in the worlds she crosses into, like in a crossover with the Star Wars universe.
Another plot twist might be that Kushina Uzumaki has a secret power that she's been hiding, and Naruto Uchiha is the only one who can help her fully unlock it. However, unlocking this power comes with a great cost that they both have to face together.
Well, a frequent theme is the exploration of Naruto's new - found godlike abilities in relation to his love for Kushina. It could be that his powers are somehow connected to his feelings for her. Another common aspect is the emotional healing that comes from their relationship. Naruto may have had a tough life, and his connection with Kushina in these fanfictions can be a source of comfort and growth. Additionally, there might be themes of heroism, where Naruto, with his godlike powers, is seen as a hero in Kushina's eyes and vice versa.
One common theme is the idea of forbidden love. Since Mikoto is from the Uchiha clan and Naruto has his own complex identity in the Naruto world, their relationship might be seen as going against the norms or expectations of their respective groups. Another theme could be redemption. Maybe Naruto helps Mikoto or the Uchiha clan in some way through their relationship, or vice versa. Also, time - travel is sometimes a theme, where Naruto gets to interact with Mikoto in a different time period.
One common theme is redemption. Sasuke has done some not - so - great things, and Naruto's love helps him find his way back. Another is the power of friendship turning into love. Their strong bond as friends is a starting point. And often there's the theme of overcoming differences, like Sasuke being from the Uchiha clan and Naruto being an outcast in a way.
One aspect to consider in Naruto and Kushina Uzumaki fanfiction is their relationship. Kushina was Naruto's mother. Fanfictions often explore how their bond could have been different if she had survived. For example, she could have taught Naruto more about the Uzumaki clan's secrets. This would have given Naruto an even greater power boost and a deeper understanding of his heritage.