The relationship between the Naruto universe and the Yugioh universe might be severely damaged. There could be a rift that affects not only the characters directly involved but also the overall balance between the two fictional worlds. Maybe there would be crossovers of characters trying to fix the situation or make things worse.
Naruto would likely experience a great deal of emotional turmoil. He has always looked up to Jiraiya as a mentor and father figure. So, this betrayal could shatter his trust in people and make him more cynical. He might also become more withdrawn and less likely to open up to others in the future.
He might face immediate retaliation from Chaos's forces. They could be extremely powerful and Percy would have to fight for his life.
One consequence could be a breakdown in their friendship. Harry might feel extremely hurt and isolated, which could affect his ability to fight against the dark forces. He may become more withdrawn and less trusting of others in general.
It can lead to emotional distress for the father. Imagine a father had a secret about a past mistake, and his son betrayed that secret. The father would feel ashamed and embarrassed all over again. Also, it might cause family conflicts. If a father's financial secret was betrayed by his daughter, there could be arguments and tension within the family about money matters.
One consequence would be a major shift in the power balance in the One Piece world. The Marines would be severely weakened, and pirates might become more bold. Another consequence could be that Naruto would become a huge target for both the remaining Marines and other powerful forces in the One Piece world.
The consequences would be disastrous. Xenomorphs are extremely aggressive and dangerous creatures. They would likely start attacking the people in Naruto's world. Villages would be in chaos as they try to fend off these alien threats. Naruto would probably feel a great sense of guilt for creating such a menace.
The most immediate consequence would be the reaction from Naruto's friends. Sasuke, for example, would likely go on a quest for revenge. He has a deep bond with Naruto and would not let his death go unpunished. Sakura would also be devastated and might lose faith in the idea of peace between the villages.
The Akatsuki would surely be affected. They would lose one of their members, which could disrupt their plans. Also, it might change the way other characters view Naruto. Some might see him as a more formidable threat, while others might see him as a hero for taking out a dangerous enemy.
If Naruto dies at birth in fanfiction, it would have a huge impact on the story's positive themes. Naruto was a symbol of perseverance and the ability to overcome one's past and hardships. His death would mean that those themes would be lost. Also, the Akatsuki's plans regarding the Nine - Tails would be disrupted. They might turn their attention to other 'jinchuriki' more quickly. And characters like Iruka, who played an important role in Naruto's life, would have a completely different story arc as they would not have Naruto to mentor and befriend.
He would likely be seen as a traitor by the village. The villagers, who once saw Naruto as a hero - in - the - making, would now turn against him. He'd be hunted by the ninja forces of Konoha.