Well, in some fanfiction concepts, Naruto might have some sort of mental breakthrough. Maybe he has a deep connection with the Nine - Tails due to some special training before the Chunin Exams. This connection allows him to access and control all of the Nine - Tails' power without being completely overrun by it.
In such a fanfiction scenario, Naruto would be extremely powerful. He could easily overpower his opponents during the Chunin Exams. The other genin would be in awe or extreme fear. His control over the ten - tails' power would likely be a major plot point, as it's such a vast and dangerous amount of chakra.
The other genin would be in awe. They would see Naruto as an almost unbeatable force. Some might be scared, like those who are not used to seeing such a powerful display. For example, the weaker genin might feel completely outclassed.
In a fanfiction where Naruto has 10 tails during the Chunin Exams, the story would be turned on its head. For starters, Naruto's growth arc that we see in the original series would be altered. He wouldn't have to struggle in the same ways to gain power. During the Chunin Exams, instead of facing challenges from his peers, he might face challenges from the entire ninja world. The Akatsuki, for example, would be very interested in him. His training would be more about controlling the ten - tails' power rather than learning basic ninjutsu. His friends and teachers would have to adapt to this new Naruto. And Naruto himself would have to deal with the isolation that often comes with great power. The Chunin Exams would no longer be a simple test but a stage for a much larger power struggle.
Well, one thing that could happen is that Naruto, with his knowledge of future events, could easily ace the written part of the Chunin Exams. He might also be able to prevent some of the chaos that Orochimaru caused during the exams. For example, he could warn the proctors about Orochimaru's infiltration in advance.
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.
In this fanfiction scenario, Naruto and Yugito could have some really interesting interactions during the Chunin Exams. Maybe they start off as rivals, each determined to prove themselves in the exams. Naruto with his unwavering determination and Yugito with her unique skills. They might end up in a match against each other, and through the battle, they gain a newfound respect for one another's abilities.
One idea could be that Naruto forms an unexpected alliance with Anko during the Chunin Exams. Maybe they team up to uncover a hidden plot within the exams that threatens the safety of all the genin. Anko, with her experience, could help Naruto see things from a different perspective and he, in turn, could inspire her with his determination.