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.
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 interesting 'Lord of the Rings crossover vampire fanfic' could be 'The Blood - Ring Alliance'. In this fic, the vampires are from a different realm and find themselves in Middle - earth during the events of 'Lord of the Rings'. They initially try to stay out of the main conflict but end up getting involved in unexpected ways. It has some great character development for both the LOTR characters and the vampires.
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.
One idea could be a vampire character who is drawn to the power of the One Ring. Maybe this vampire, being a creature of the night and often associated with darkness and power -hunger, sees the ring as a means to gain ultimate power in Middle - earth. For characters, you could have a half - vampire, half - elf who struggles with their dual nature while being caught in the events related to the ring.
To write a good vampire Lord of the Rings crossover fanfiction, you need to focus on character development. If you're introducing a vampire lord, make him a complex character. Give him motives that are more than just 'I want to rule the world'. Maybe he has a tragic past that led him to his current state. Also, make sure the language you use fits the tone of both worlds. The Lord of the Rings has a very specific, almost archaic style of speaking in places, and your vampire characters should also have a voice that is consistent with their nature. And don't forget about the pacing. You don't want to rush the story, especially when it comes to the big moments like battles or revelations about the ring.
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.
One common theme is the clash of different cultures. Buffy comes from a modern world with a certain set of values and fighting styles, while Middle - earth has its own ancient and more traditional ways. So, the stories often explore how these differences play out when she arrives there.
Yes, in many ways 'Shadow of War' can be considered one of the best 'Lord of the Rings' fanfic - like works. It expands on the rich lore of Middle - earth. The game has a vast world filled with characters both familiar and new. It continues the story in a way that feels true to the original spirit of Tolkien's work, with epic battles and complex relationships.
To write such a fanfic, you could take the serious themes and turn them on their head. For instance, have the powerful magic items malfunction or have the epic battles end in absurd ways. Just let your imagination run wild and have fun with it!