Well, perhaps in this fanfiction, the world is on the brink of a new, greater threat. Naruto realizes that he needs the power of the Uzumaki clan in a more direct way. He discovers a prophecy that says only by uniting with an Uzumaki in the purest way - marriage - can he gain the strength to save the world. Kushina is brought back in a spiritual form that can become corporeal. As they work together to face the new threat, they fall in love and get married, with their union bringing a new era of peace and strength to the Hidden Leaf Village.
One possible plot could be that Naruto discovers a way to travel back in time and decides to save his mother, Kushina. As he gets to know her better during this time - saving her from threats and sharing his future knowledge with her - their relationship deepens into love, and they end up getting married. It could also involve Naruto having to deal with the consequences of changing the past in terms of how it affects the future he came from.
Well, in some fanfictions of 'naruto marries kushina', there could be a plot where Naruto somehow travels back in time. This allows him to meet Kushina in her younger days. He then uses his knowledge from the future to win her heart in a very unique way. Maybe he shows her all the great things that will happen to their son in the future, which makes Kushina fall for him.
In a time travel fanfiction where Naruto marries Kushina, the impact on the Naruto world would be multi - faceted. Genetically, it's a very strange situation. But if we look past that, politically, their union could bring about peace faster. Since Naruto has the ideals of the future and Kushina has the influence of her clan in the past. Socially, it would shock many. People would have to adjust to this new relationship. And in terms of the ninja arts, Naruto could teach Kushina some future techniques, and she could pass on her unique skills to him, changing the way battles are fought in that time period.
One possible plot could be that Naruto, with his strong will and unique powers, enters the world where Rias exists. Their meeting might be accidental, perhaps during some sort of interdimensional rift. Naruto's sense of justice and Rias's leadership in her own group could lead to them having mutual respect. As they get to know each other more, they find that they share common goals in protecting the weak and maintaining balance. Eventually, they fall in love and decide to get married. Their union could bring about a new era of cooperation between the two different fictional worlds, with Naruto teaching some of his ninja techniques to Rias's group and Rias sharing her knowledge of magic with Naruto's friends.
Well, one possibility could be that Naruto somehow enters the world where Koneko exists. Maybe there's a strange jutsu gone wrong that transports him. They meet, and Naruto's kind and determined nature attracts Koneko. Eventually, they fall in love and get married. Naruto might introduce Koneko to his friends in Konoha, and she could share her unique skills with them.
One possible plot could be that Naruto grows up with a strong mother figure. Kushina might teach him early on about his Uzumaki heritage, which could make him more confident. He might also learn her unique chakra control techniques much earlier, leading to him being more advanced in his ninja skills at a younger age.
Naruto could develop a stronger sense of responsibility. He is marrying Kushina, so he has to take care of her and think about their future. This might lead to him being more cautious in his actions. Kushina, on the other hand, may develop a more open - minded attitude. She might start to accept new ideas and ways of life that Naruto brings to her.
Well, one possibility could be that Naruto has a different set of skills or personality traits due to having Minako as a mother. Maybe he inherits some unique jutsu from her side of the family. He could also face different challenges in his journey to become Hokage, like dealing with the expectations that come from having two strong and perhaps different heritages.
Well, in such a fanfic, the fem Harry Potter might be on the run from some dark wizards and accidentally end up in the Naruto universe. Naruto rescues her from an initial danger. They start to train together, with her teaching him some basic magic and him teaching her ninja moves. As their bond grows stronger, they fall in love. For their marriage, they have to find a way to combine the traditions of both their worlds, which is no easy feat. There are also antagonists from both universes who try to stop their union because they fear the power they would have together.
One plot twist might be that Aphrodite loses her powers when she falls in love with Naruto. This would change their relationship dynamic as she has to rely on Naruto in ways she never expected. Also, there could be a twist where a prophecy in Naruto's world predicts that his union with Aphrodite will either save or destroy both their worlds, and they have to figure out which it will be.
One possible plot could be that Naruto grows up with a unique connection to the fem Kyuubi. Since his mother Kushina was also linked to the Kyuubi, Naruto might have an even stronger bond. He could learn special jutsus from the fem Kyuubi's chakra, which makes him stand out among his peers in the ninja academy. His relationship with the fem Kyuubi could be like a mentorship, guiding him on his path to become a great ninja.