Well, it could be about Naruto having to deal with the strict and fiery nature of Akainu as his father. Maybe Naruto has to adapt to a more military - style upbringing while still holding onto his own ninja values.
The plot might involve Naruto struggling to fit in with the Akainu - influenced family or group. He could be constantly at odds with Akainu's ideas, yet slowly learning some useful skills from him. For example, Akainu's strong sense of justice, though different from Naruto's ninja world's concept, might shape Naruto in a new way. And there could be conflicts with Naruto's friends who don't trust Akainu or his family. Also, Naruto might have to face enemies who target him because of his relation to Akainu.
One possible plot could be that Akainu attacks the Straw Hat's new island, endangering Luffy's friends. Luffy, filled with rage, challenges Akainu. After an intense battle, Luffy discovers a new form of his Gear ability that allows him to withstand Akainu's magma and finally defeat him.
Naruto's character would likely become more complex. He might develop a harsher edge due to Akainu's influence, but still retain his core kindness.
One common theme is the clash of ideologies. Akainu has a very strict and uncompromising view of justice in his original story, while Naruto has a more forgiving and rehabilitative view. So when they interact in fanfiction, this clash often forms a central theme.
In a 'naruto son of bellatrix fanfiction', perhaps Naruto has some of Bellatrix's wild and unpredictable nature. He could be on a journey to discover his true identity and how he came to be Bellatrix's son. This might lead him to explore the secrets of the wizarding world and his own ninja abilities in a new light.
Well, one possibility could be that Naruto inherits some of Gilgamesh's arrogance along with his power. Maybe he has a special ability to summon ancient Babylonian weapons. And he could use this in his battles in the Naruto world, like against the Akatsuki.
One possible plot could be that Naruto discovers his true heritage as the son of a princess from a hidden kingdom. He then has to deal with the politics and expectations of the royal family while still maintaining his ninja ways. Maybe he has to protect the kingdom from a new threat using his ninja skills.
In such a fanfiction, perhaps Naruto could be shunned by the village from the start. His 'devil' heritage might give him strange powers that he has to hide. He could struggle with self - identity, different from the Naruto in the original who is seen as a hero. Maybe he has to fight against the prejudice of the people who believe the devil's son can only bring destruction.
Well, it could be about Naruto having powers related to Hades on top of his ninja skills. Maybe he can control the dead or has some sort of underworld - like abilities that he uses in battles against the Akatsuki. He might also have to deal with the stigma of being the son of Hades in a world that doesn't understand such a thing.
Maybe Naruto is raised in Gotham instead of Konoha. He could inherit some of Catwoman's skills like stealth and agility, while still having his own ninja powers. He might fight crime in Gotham using a mix of his ninja techniques and Catwoman - like thievery skills, but for good causes.
Perhaps the story involves Naruto's journey to discover his true heritage as the son of Pegasus. He might face challenges from those who don't believe or accept his origin, and he has to prove himself. Along the way, he could make new friends or allies who help him in his quest.