His speed would likely be a huge advantage. He could be faster than most wizards in combat or when running from danger. For instance, in a duel, his quick reflexes would allow him to dodge spells more easily.
Minato could be developed further by exploring his time as the Fourth Hokage more deeply. For example, show his political decisions and how they were influenced by the presence of the Kyuubi. Also, his relationship with other villages could be explored, especially in relation to the Kyuubi's power. Maybe he had to make some tough calls to protect the village from those who might want to use the Kyuubi for evil.
Kushina and Minato's love story is truly a heartwarming one. Minato was a prodigy in the ninja world. When he first saw Kushina, he was captivated by her. Kushina, on the other hand, was initially a bit stubborn towards him. But as time passed, Minato's consistent care and his heroic deeds won her heart. They had a relationship built on mutual respect, admiration, and a deep emotional connection. For example, Minato would always be there for Kushina when she faced difficulties, whether it was dealing with bullies or more serious threats. This made Kushina realize how much he meant to her, and they went on to have a loving relationship that was envied by many in their village.
They would be empathetic. Minato, as Naruto's father, would especially feel a deep sense of pain seeing his son struggle. He would want to reach out and comfort Naruto during his lonely times when the village shunned him because of the Nine - Tails.
The fanfic could portray Naruto as having greater physical strength and endurance. Maybe he can take more hits and keep fighting, while Minato might get tired more easily. Also, Naruto's strategic thinking in combat could be shown as superior, allowing him to outwit Minato in battles.
Minato would likely be extremely shocked. Naruto is his son, and the idea of Naruto attacking him would be completely unexpected. He would probably try to talk to Naruto first, to find out what is wrong and why he is being attacked.
Perhaps Minato has been corrupted by power. In the fanfiction world, he might have come across some source of power that has twisted his mind. By sealing Naruto's chakra, he could be trying to take that power for himself. It could also be related to some prophecy that he misinterprets. He thinks sealing Naruto's chakra is the key to saving the world, but in reality, it's the opposite.
If Minato time - travels, it could change a lot. For instance, if he prevents the Nine - Tails attack, Naruto would grow up in a very different environment. He might not be the underdog he was in the original story. Also, if Minato changes things during the Uchiha clan's situation, Sasuke's story would be completely different. Konoha's political situation would also be altered. There would be less animosity between different clans perhaps.
Yes, there are some fanfictions with this concept. It's an interesting twist on the original Naruto story. In these fanfictions, the relationship dynamics are completely different. Naruto being Minato's daughter would change how she (as Naruto) interacts with other characters like Sasuke and Sakura. For example, Minato might be more protective in this scenario, and Naruto's journey as a kunoichi could have different challenges and developments compared to the original story where Naruto is male.