Well, Gojo could be a super powerful outsider. Maybe he comes to the Naruto world to study its unique chakra system. His Infinity ability would be a game - changer. He could use it to easily deflect most ninjutsu attacks. And his Six Eyes could help him detect hidden enemies or traps that normal shinobi might miss.
Toge Inumaki is important too. His special cursed speech ability makes him stand out. Also, the principal of the school, Masamichi Yaga, is likely to be important as he is in a position of authority and has an influence on Gojo and the other students. There could be other characters like the members of different clans that also play roles in the complex web of the story.
Naruto would become more confident. Gojo's power is extremely strong, and having it would make Naruto feel like he could handle almost any situation. He'd also become more strategic as Gojo's power requires a different approach to combat compared to his normal ninja skills.
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