The plot could be that Naruto is somehow transported to the Hellsing universe. He starts off as an outsider but quickly proves his worth. His rasengan could be adapted to be effective against vampires, perhaps by infusing it with holy water or some other vampire - weakening element. Naruto's presence could also introduce a new dynamic to the relationships within the Hellsing organization, and he might even form an unexpected bond with Seras Victoria as they both have a strong sense of loyalty and a desire to protect the innocent.
Naruto's speed and agility from his ninja training would be very useful in the Hellsing world. He could easily dodge attacks from vampires and other creatures. His ability to use chakra to enhance his physical strength means he could hold his own in close - combat situations. For example, he could punch a vampire hard enough to send it flying. Also, his summoning jutsu could bring in some interesting allies to help the Hellsing team in their battles.
Well, in such a fanfiction, Harry Potter might bring a new perspective to the Hellsing crew. He comes from a world where magic has different rules and ethics. His presence could lead to some internal conflicts within Hellsing as they debate whether to trust his 'alien' magic. Also, Harry might be shocked at the extreme measures Hellsing takes against vampires and other supernatural beings, and try to find a more 'humane' solution while still protecting humanity.
Immortality in Naruto - Hellsing fanfiction can bring a whole new level of storytelling. In Naruto, some characters are effectively immortal through means like the tailed beasts' chakra. In Hellsing, vampires are immortal. Combining these, a story could be about a character trying to find a way to end the immortality curse. Maybe Naruto uses his sage mode to understand the nature of vampiric immortality in Hellsing.
One possible crossover in Naruto and Hellsing fanfiction could be the sharing of powers. For example, Naruto's ability to use chakra could be combined with the vampiric powers in Hellsing. Maybe a character from Naruto gets turned into a vampire and has to deal with the new powers and the moral implications in the Hellsing universe.
One common theme is the clash of different power systems. In Naruto, there are chakra and ninja techniques, while in Hellsing, there are vampires and powerful weapons. Fanfictions often explore how these different power systems interact when the two worlds meet.
One idea could be a crossover where Naruto is somehow transported to the Hellsing universe and meets Seras. Maybe Naruto's unique powers, like his shadow clones, could be used in battles against the vampires in the Hellsing world. Seras, with her vampire abilities, might initially be seen as an enemy to Naruto but they could end up teaming up.
One interesting Naruto Hellsing werewolf fanfiction could be where Naruto has werewolf - like powers in the Hellsing universe. For example, a story might explore how Naruto's tenacity and his newfound werewolf abilities interact with the dark and vampire - filled world of Hellsing. Maybe he teams up with Alucard to fight a common enemy.
Well, in a Naruto - Overwatch crossover fanfiction, Naruto's presence would shake things up. His determination and never - give - up attitude would inspire the Overwatch team. His ninjutsu could be adapted to fit the Overwatch universe. For example, he could use his chakra control to enhance the power of some of the existing Overwatch weapons. Also, his relationships with the other characters would be interesting to explore. He might form a strong bond with Tracer due to their similar energetic natures.
He'd bring a new sense of hope. The Hellsing organization is often mired in dark and violent affairs. Naruto's positive attitude could be a breath of fresh air for the members. For example, Seras might be inspired by Naruto's determination to protect those he cares about.