The Akatsuki would be highly affected. Since Naruto has future knowledge, he could stop their plans before they even start. Also, his friends like Sasuke would be affected as Naruto could prevent Sasuke from going down the wrong path.
The Hidden Leaf Village as a whole would be among the most affected. Naruto could use his power to improve the village's defenses, education system, and relations with other villages. The elders of the village might also have to change their ways as Naruto, with his godlike status, would have a lot of influence. Another group affected would be the other jinchuriki. Naruto could potentially free them from their suffering much earlier in time.
Definitely Hermione. Since she's Harry's closest friend and very intelligent, she would be deeply involved in any changes Harry tries to make. Also, Snape. Harry's actions in the past could completely change his relationship with Snape. And of course, Voldemort. If Harry goes back far enough, he could potentially stop Voldemort's transformation into the evil wizard he became.
Obviously Naruto himself is the most affected. He has to deal with the knowledge of the future and the changes he wants to make. Sasuke is also important. Naruto might try to change Sasuke's path to prevent him from going down the dark road of revenge. Kakashi could be another one. Naruto may share his future knowledge with Kakashi to make him a more effective teacher and ninja.
His friends would be the most affected. For instance, Shikamaru, who is used to Naruto's normal self, would have to adjust to this new and somewhat spooky Naruto. He might have to come up with new strategies to deal with Naruto's new abilities and behavior.
His friends would be the most affected. People like Sakura and Kakashi who know Naruto well. Sakura is used to Naruto's kind - hearted and determined self. If he starts acting like Grimmjow, she'd be very confused and worried.
Sasuke would be one of the most affected. He and Naruto had a complex relationship, from being rivals to friends. Naruto's death would leave a huge void in Sasuke's life. Also, Hinata. She loves Naruto deeply, and losing him would be devastating for her.
Naruto's powers, especially his Nine - Tails chakra, could have a huge impact. He could use it to fend off stronger enemies much earlier. Hinata's Byakugan would give her an edge in predicting enemy moves. They could use their powers together to change battles that were originally lost. For example, Naruto could use his Rasengan more effectively with Hinata's support and knowledge from the future.
The interaction between Naruto and Thor would be captivating. Thor, a god himself, would be curious about Naruto's godlike powers. They could compare their powers, like Thor's thunder and Naruto's Rasengan. And then there's the potential interaction between Naruto and Hawkeye. Hawkeye's precision with his arrows could be combined with Naruto's ability to target enemies precisely. Maybe Naruto could learn some new aiming techniques from Hawkeye, and Hawkeye could learn about Naruto's chakra - enhanced senses for better targeting.
It's really hard to say. Naruto with his godlike powers would be extremely powerful. He can do things like create massive Rasengans and has near - unlimited chakra. But Superman in the Justice League also has incredible strength, speed, and heat vision. He can fly at supersonic speeds and is nearly invulnerable. However, if Naruto's godlike form gives him the ability to manipulate time and space like some of the Otsutsuki in his world, he might have an edge over Superman.
It could be Naruto. His godlike form in Naruto already gives him incredible power. If he were to gain quirks on top of that, he would be extremely formidable. His ability to create thousands of clones and his vast chakra reserves combined with a powerful quirk would make him a top - tier character.
Naruto would probably be the most interesting. Since it's a 'godlike' scenario, his already - strong will and determination would be amplified. He'd be using his new - found god - like abilities in really creative ways, like combining multiple jutsus in one attack. His character development would be really exciting to follow as he tries to balance this new power with his regular ninja self.