Since Orochimaru had many experiments and secrets, his death at Naruto's hands in the Chunin Exams fanfiction could lead to a scramble for his research. Other villages or even some rogue ninjas might try to steal his notes and facilities. In Konoha, Naruto might be pressured to reveal what he knew about Orochimaru's plans and secrets. This could put him in a difficult position as he may not know everything. Also, Sasuke, who had a connection with Orochimaru, might have a complex reaction. He could be angry at Naruto for killing Orochimaru, or he could see it as a sign of Naruto's strength and be motivated to become stronger himself.
In this kind of fanfiction, Naruto might have used his new and powerful jutsu that he developed secretly. Maybe it was a super - enhanced Rasengan with some special chakra nature added to it, which was strong enough to overpower Orochimaru.
He might kill an enemy shinobi from another village. For instance, if there is a particularly aggressive and cruel shinobi from the Sand Village during the Chunin Exams who poses a great threat to Naruto's friends or the Leaf Village in general, Naruto could be forced to kill him in self - defense or to protect others.
In such a fanfiction, the plot could involve Naruto being pushed to the extreme during the Chunin Exams. Maybe he witnesses some great injustice or threat to his friends that makes him cross his moral line and kill. For example, if an enemy tries to assassinate Sasuke during the exams and Naruto, in a fit of rage and desperation to protect his friend, uses a powerful jutsu that ends up killing the attacker.
One consequence could be a shift in the power balance among the ninja villages. Since Orochimaru was a powerful and feared figure, his death might cause some chaos as his former allies or subordinates try to either avenge him or claim his resources. For example, some of his secret labs and experiments might be up for grabs, leading to potential conflicts.
One possible consequence could be a huge shift in the power dynamics among the ninja villages. Since Naruto was seen as a potential strong force, his death might make Konoha more vulnerable. Also, his friends like Sasuke and Sakura would be deeply affected. Sasuke might be driven further into his quest for power in a more reckless way out of revenge or a sense of loss. And Sakura would likely be devastated, perhaps changing her path from a healer to someone more focused on vengeance as well.
Yes, there might be such fanfics out there. Fanfic writers often explore alternative storylines, and this would be a very dark and unexpected twist to the original Naruto story. It goes against the strong bond and rivalry that Naruto and Sasuke have in the canon, but that's the allure of fanfiction - to see what could happen if things took a drastically different turn.
He could be disqualified, of course. In the Chunin Exams, integrity is important. If caught cheating, Naruto would likely face immediate expulsion from the exams. This would also damage his reputation among his peers and mentors, like Kakashi and Iruka. They have high hopes for Naruto, and cheating would be a huge disappointment.
One consequence could be a shift in the power balance in the ninja world. With Orochimaru gone, his followers might scatter or try to seek revenge. This could lead to new conflicts.
One memorable moment could be when Hinata finally shows her true strength in a fight during the Chunin Exams in the fanfiction. Maybe she overcomes her shyness and uses a new jutsu to surprise everyone. For Naruto, it could be when he defends Hinata from some bullies during the exams. This shows his loyalty and growing feelings for her.
A fanfiction might explore the idea of Naruto and Kurenai teaming up during the Chunin Exams. Kurenai, being an experienced kunoichi, could guide Naruto through the more complex parts of the exam. They could face off against some unexpected opponents together. Naruto's raw power combined with Kurenai's intelligence and genjutsu skills would make for an exciting story.