Yes, there are likely to be such fanfictions in the vast world of fanfiction. Many fans like to create alternate family relationships and storylines for their favorite characters.
Well, in fanfiction, anything can happen. Just because it says Harry is Uryu's brother doesn't necessarily mean it's going to be a traditional brother relationship. It could be a metaphorical brotherhood, or it could be a result of some crazy plot device like a cross - over between two different universes. So, it really varies from one fanfiction to another.
If Harry grew up as Lily's brother, it would completely change the dynamic. Firstly, Voldemort might not target him in the same way. Since the prophecy was about a child born at a certain time, the circumstances around his family would be different. He might grow up with more love and protection from his family. Also, his relationship with Snape would be very different. Snape loved Lily, and if Harry was her brother, Snape might be more protective of Harry instead of being so hostile.
Sirius Black might be involved. As Harry's godfather and James' friend, he might have some knowledge about the trunk. He could help Harry understand the significance of the items in it. Also, Dumbledore could be involved. He always seemed to know a great deal about everything, and he might have some information about Lily's trunk that could help Harry on his journey of discovery.
In most of the fanfiction, this is just a very strange and out - of - the - ordinary concept. There is no evidence in the original books to support such a relationship. J.K. Rowling has clearly established the family tree, and Harry is a Gryffindor like his father, with his mother's love protecting him from Voldemort. So in the context of the real story, it's completely untrue.
There could be. Fanfiction often explores alternative universes and relationships. But this concept goes against the canonical story where Harry is James and Lily's son. In fanfiction, authors can play with these ideas freely, but it may be controversial among some fans who prefer to stick to the original storylines.
In the original 'Harry Potter' canon, Harry is not Voldemort's son with Lily. Fanfiction can be full of strange and alternative takes on the story. But the original story has a clear family tree for Harry. His father was James Potter, and his mother was Lily. Voldemort was the one who killed his parents, not a potential co - parent. Fanfiction writers might write this for shock value or to explore different character dynamics, but it's not part of the 'true' Harry Potter story.
Yes, there might be such fanfiction out there. The Harry Potter fandom is vast and full of creative interpretations. Some fans like to explore unusual family relationships in their fan - created stories. This concept could lead to very interesting plotlines, like how it would change the dynamics between Harry and the Death Eaters if he was related to Bellatrix in this way.
Yes, there are likely some fanfictions with this concept. The Harry Potter fandom is very creative, and writers often come up with unique relationships between characters. Some might explore the idea of Snape being Harry's brother to add new layers of drama, mystery, and character development to the story.
There could be. Fanfiction is all about taking existing characters and creating new scenarios. Given the popularity of both the Harry Potter universe (assuming Harry here is from that) and Superman, it's not a stretch to think that someone has written a story where they are brothers. However, it may not be a very common one as they come from very different fictional worlds originally.