Yes, there are likely fanfictions out there with this concept. Fanfiction platforms have a wide variety of creative takes on existing characters. You can try searching on popular fanfiction sites like Archive of Our Own or FanFiction.net. Just type in relevant keywords like 'female Naruto shrine maiden' and browse through the results.
Obviously, Naruto himself could be one of the main characters. He would interact with the shrine maiden, perhaps learning about her culture and powers. Another could be the shrine maiden, of course. She would be at the center of the story with her unique abilities and background.
Perhaps it's about how her being a shrine maiden changes her relationship with Sasuke or other characters. For instance, they might view her in a different light, with more respect for her spiritual role. It could also explore how she uses her shrine maiden powers, if any, in battles or in solving village problems. Also, it might show her learning the ways of the shrine maiden, like the proper ceremonies and the significance of the shrine she is associated with.
Another option is a rival village that discovers the potential of the shrine maiden's powers. They send their best ninja to kidnap her and force her to use her powers against the Hidden Leaf. This antagonist would be more of a political and military threat, as they are using the shrine maiden as a tool to gain an advantage in the shinobi world.
One idea could be that the shrine maiden has a special power that can heal the wounds of the ninja in Naruto's world. This power becomes crucial during a big battle, like the Fourth Great Ninja War. She uses her abilities to save many lives, and in the process, she forms a special bond with Naruto and his friends.
One idea could be a shrine maiden who has the power to communicate with the spirits of past shinobi. She teams up with Naruto to solve a mystery that threatens the Hidden Leaf Village. The spirits might provide clues that only she can understand.
In a shrine-themed manga about male relationships, you might expect to see a lot of internal conflicts and external obstacles that the characters have to overcome together. The setting of the shrine could add a spiritual or symbolic dimension to their connections. Also, the story could delve into the historical or cultural significance of the shrine and how it influences the characters' interactions.
I have no clear idea about 'Spain Maiden Manga Hentai'. It might be a manga that combines elements of Spanish culture and maiden characters in an adult-oriented way. But that's just a guess based on the words given.