Some fanfictions might have a plot where Goku and Naruto are in a training - like fight. They exchange techniques and learn from each other. For example, Goku could teach Naruto about ki control, and Naruto could show Goku how to use chakra in a more strategic way. Their fight could be less about winning and more about mutual growth and respect for each other's abilities.
Perhaps the reincarnated character has to face a situation where they are not fully accepted as Goku by his friends and family. They then have to prove themselves not just in terms of strength but also in terms of character, and in the process, they form new and deeper relationships with the Z - fighters.
One interesting plot could be Goku and Fem Frieza having to team up against a new, powerful enemy. Maybe this enemy is threatening both of their planets or has some power that neither can defeat alone. Another plot could be Fem Frieza falling in love with Goku and trying to change her evil ways to be with him, but struggling with her past and her reputation among the villains.
In some 'oc son of goku fanfiction', a common plot is the OC's struggle with his identity. He is the son of Goku, a great hero, but he wants to make a name for himself. So he might embark on a quest to find a new form or a new fighting style that is all his own. Also, there could be a plot where he has to deal with the jealousy of other Saiyans who feel he gets special treatment due to his father.
One interesting plot could be Goku having to balance his training and his relationships with the various characters in his harem. For example, he might have to deal with the jealousy among the girls when he spends more time with one over the others.
One interesting plot twist could be that Goku and Beerus end up teaming up instead of fighting. Maybe they discover a common enemy that is even more powerful than them. Another could be that Beerus loses his power temporarily and Goku has to protect him from other villains while also trying to figure out how to return Beerus' power.
One interesting plot could be a competition between them for a powerful magical artifact. Percy uses his water - based powers, Jason his lightning and flight, and Nico his control over the dead to outwit each other in a race to find it.
One possible storyline could be that Naruto is somehow transported to Goku Black's universe. There, he has to face Goku Black who sees him as an intruder. Naruto would have to quickly learn about Goku Black's powers and find a way to fight back using his ninja skills. Another storyline could be that a powerful villain creates a rift between their two universes and pits them against each other. They start off as enemies but then realize they are being manipulated and team up to fight the real villain.
One interesting Naruto and Goku fanfiction could be a story where they team up to fight a powerful new villain. Maybe a being from another dimension that neither of their worlds has faced before. They combine their unique powers, Naruto's ninjutsu and Goku's ki attacks, to take on this threat.
One interesting plot could be a competition between Peter and Flash in a science fair. Peter uses his intelligence and some of his spider - powers subtly to create an amazing project, while Flash tries to outdo him with his over - the - top showmanship. Another plot might be a race where Peter, without using his full spider - speed, still manages to keep up with Flash who is the school's track star, leading to Flash being both frustrated and a bit in awe of Peter.
One interesting plot could be that Batman and Catwoman are forced to team up against a greater threat in the fanfiction. Maybe a new supervillain emerges who is more powerful than any they've faced before, and they have to put aside their differences to save Gotham.