Another character Naruto could interact with is Weiss. At first, they might not get along because of their different personalities and backgrounds. But as the story progresses, they could come to respect each other. Naruto could help Weiss become more open - minded, and Weiss could introduce Naruto to the more refined aspects of huntsmen society, like the importance of family names in that world.
He could interact with Ruby. Naruto's energetic and positive nature would contrast well with Ruby's enthusiasm for being a huntress. They could learn from each other's combat styles, like Naruto showing Ruby some of his acrobatic ninja moves and Ruby teaching Naruto about using a scythe.
Well, it could be that Naruto, with his ninja skills, enters the world of huntsmen. Maybe he teams up with some of the huntsmen characters and uses his shadow clone jutsu in unique ways during hunts. For example, he could send clones to scout out the area while he focuses on a more difficult part of the mission.
He could interact with Luffy. They both have a strong sense of justice and a love for adventure. Their meeting would be really interesting as they could exchange stories about their different worlds and fight side by side against the common enemies in Dressrosa.
He could also interact with the scientists on Pandora. They might be interested in Naruto's abilities and study him. Naruto could in turn learn about their technology, which is so different from what he has in his own world. He might even help them solve some problems they have on Pandora using his ninja wisdom.
Tsunade would definitely be one. As the most renowned medical ninja in the village, she could either be Naruto's mentor or a colleague. They could exchange medical knowledge and experiences.
He could also interact with the new generation of ninjas in his own village who might see him as a relic of the past at first. But as they get to know him, they learn valuable lessons from his experiences. He could train them in unique ways that combine his old - school ninja techniques with the new knowledge and abilities that the new generation has developed.
Naruto might interact with Eostia's warriors. They could train together, Naruto showing them his ninja combat skills and them teaching him about Eostia - style combat. There could also be some mysterious characters in Eostia, like an old hermit who has some knowledge about Naruto's sudden appearance in their world and could guide him on his journey in Eostia.
He could interact with his old sensei, Iruka. Iruka was an important figure in Naruto's life, and as a ghost, Naruto might visit Iruka to give him some comfort or to seek advice. Since Iruka was always there for Naruto when he was alive, their connection could still exist in the afterlife.
In a crossover with the Attack on Titan world, characters like Eren could interact with Naruto. Eren, with his strong will to fight for freedom, could learn from Naruto's experience as a father and a hero. Levi might also be interested in Naruto's combat skills and how he trains his child in the ways of the ninja.
He could interact with Mei Terumi, the Mizukage. She might be initially cautious of Naruto but then see his potential and work with him. Also, Chojuro, as he is one of the important ninjas in Kiri. They could train together or go on missions side by side.
Well, Kakashi could play an important role. Since he was Naruto's mentor, he would be very curious about Naruto's sudden change to a nobody. He might secretly investigate what caused this. Shikamaru could also interact with Naruto. Shikamaru is smart and observant. He might notice some small details about Naruto that others miss, and try to figure out the mystery behind Naruto becoming a nobody. Also, Rock Lee could be in the story. Lee might see Naruto as a new opportunity to spread his 'youth' spirit, not knowing Naruto's past.