It could be Odin. Odin is known for his wisdom and he might see potential in Percy. He could adopt Percy to add a new element to the Norse pantheon or perhaps he has a plan to use Percy's skills for some greater purpose in the Norse realm.
Maybe Loki would adopt Percy. Loki is a trickster god and he might find Percy's situation interesting. He could adopt Percy as part of one of his elaborate schemes. This would lead to Percy getting involved in all sorts of chaotic and unpredictable adventures in the Norse world.
Thor is also a likely candidate. Thor is a powerful and noble god. He might see Percy's courage and take him under his wing. Percy could then learn about strength and honor in the Norse way from Thor. And together they could face enemies that threaten both the Norse and Greek worlds if the story takes that turn.
Yes, in some fanfiction, Percy Jackson can be depicted as a fan of Norse gods. Fanfiction often takes existing characters and places them in new and different scenarios or gives them new interests. So it's possible for Percy Jackson to be into Norse gods within the creative realm of fan - made stories.
In the 'Percy is adopted by a Norse god' fanfiction, he could be given a new identity within the Norse world. This new identity might come with certain responsibilities. He may have to prove himself to the Norse community. And his friends from the Greek side might have different reactions. Some could be jealous, while others might be curious about his new life. There could also be a plot where Percy has to use his combined Greek and Norse knowledge to save both worlds from a common threat.
Well, he might gain new powers like the ability to control thunder like Thor. He could also have to deal with the Norse pantheon's politics. Maybe he'd form an alliance with Loki for some reason, who knows?
Well, in Percy's Norse god fanfiction, there might be cool elements like Thor's hammer. Maybe Percy gets to interact with it in some way, like trying to lift it. It could also feature Loki's trickery, adding some mystery and chaos to the story.
It could be a child of a minor god who has been overlooked. Maybe the child of Hecate, a young demigod with some really interesting magic powers that Percy and Artemis see potential in.
A great character pairing would be Percy Jackson with Thor. You could write about how Percy, with his water - based powers, and Thor, with his thunder and lightning, would interact. They might start off as rivals, each thinking their powers are superior, but then come to respect each other when facing a common enemy. Another interesting pair is Percy and Odin. Odin's wisdom and Percy's street - smart nature could lead to some deep conversations and interesting plot developments. And Percy with Baldr could also be good. Baldr's purity and Percy's tenacity could create a unique dynamic.
One plot idea could be Percy Jackson being sent on a quest to the Norse realms by the Greek gods. There, he has to team up with a Norse god, like Thor perhaps, to stop a common enemy that threatens both the Greek and Norse worlds. Another could be Percy getting caught in a power struggle between different Norse gods and having to use his wits and demigod powers to survive. Maybe he discovers he has some unexpected connection to the Norse gods, like a long - lost relative who was part of both worlds.
One possible story could be that Percy Jackson discovers a hidden Norse artifact while on a quest in the Greek world. This artifact makes him curious about Norse gods and he starts to study them. Another could be that he meets a demigod from a Norse - inspired camp and through their friendship, he becomes a fan of Norse gods.
It's hard to say if it's a popular concept without more context. If there's a specific community or group that focuses on Percy and Norse fanfiction, it could be popular within that niche.
One plot point could be that Harry discovers he has a connection to Thor and gains the ability to control lightning. Another could be that the Norse gods have a hidden school of magic in Asgard that Harry visits. Maybe the Sorting Hat was actually created by Odin.