A really interesting plot could be that Naruto is mistaken for a powerful wizard. He gets involved in the battle against Sauron. His Rasengan could be a powerful weapon against the orcs and other dark creatures. Also, his friendship with the characters in Middle - earth would grow as they see his loyalty and determination, much like how his friends in the Naruto world value him.
One possible plot could be Sasuke finding himself in Middle - earth. He might be mistaken for an elf at first due to his appearance. He could then get involved in the fight against Sauron. Maybe he uses his Sharingan to detect the presence of orcs or other dark forces. His ninja skills would be quite useful in battles, like his speed and ability to move stealthily.
The plot could involve Naruto characters in the Middle - earth. Maybe Naruto with his shadow clone jutsu could be used in battles against orcs. For example, he could send a horde of clones to confuse the enemy. And Sasuke with his Sharingan might be able to detect the hidden threats in the dark forests of Middle - earth. It would be a really interesting mix of the two universes' combat styles and magic systems.
One way it could work is by having Naruto characters in Middle - earth. For example, Naruto with his shadow clone jutsu could be a great asset in the battles against Sauron's forces. He could create clones to confuse the orcs and trolls. Meanwhile, characters from 'Lord of the Rings' could learn from Naruto's ninja skills. Frodo might pick up some stealth techniques from Naruto's training.
Well, often there's the element of the vampires being outsiders in Middle - earth. They usually have their own powers and motives that are different from the normal LOTR characters. For example, they might be interested in the power of the One Ring for their own reasons, like using it to enhance their vampiric abilities or gain more control over other beings.
One possible plot could be that Eragon somehow gets transported to Middle - earth. He could meet Aragorn and learn from his leadership skills. Maybe they would join forces to fight a common enemy like a new breed of dark creatures created by a combination of Sauron's magic and the dark forces from Eragon's world.
I think Naruto and Aragorn would interact well. Aragorn is a natural leader, and Naruto has leadership qualities too. They could share their experiences in leading their respective groups. Also, Aragorn could be impressed by Naruto's combat skills and his never - give - up attitude.
One idea could be that the Night King from 'Game of Thrones' somehow travels to Middle - earth. There, he might team up with the forces of Sauron, creating a double threat to the free peoples. The characters from both universes would have to find a way to work together, like Arya Stark using her skills to infiltrate Sauron's ranks while Legolas and Jon Snow lead the combined forces in battle.
Perhaps the One Ring could have an unexpected reaction to Naruto's chakra. It could either be attracted to it or repelled. This could create an interesting plot where Naruto has to deal with the power of the Ring while also trying to find a way back to his own world.
The plot of 'naruto and the 100 crossover fanfic' might center around a strange anomaly that transports Naruto to the universe of 'The 100'. Once there, he meets Clarke and the others. He starts to teach them some of his ninja techniques, like how to move stealthily or use chakra to enhance their physical abilities. In return, they teach him about their world's technology and survival skills. This exchange of skills could be crucial in their fight against the various factions vying for power in 'The 100' world.
Well, in 'lord of the rings crossover fanfic', the idea of mixing different species from other fictional works can be really engaging. For example, a crossover with the world of 'Game of Thrones'. The political intrigue of the Seven Kingdoms combined with the epic quest of the One Ring. Characters like Tyrion Lannister could meet Frodo and have some really interesting exchanges about power and survival. Or a crossover with the 'Star Wars' universe. The Force could interact with the magic in Middle - earth in a very unique way, and Jedi could potentially have their own take on the One Ring's power.