Yes, there are such fanfictions in the Harry Potter fanfiction community. Some fans like to explore alternative family relationships in the wizarding world through fanfiction.
In some fanfictions, Severus is indeed made out to be Harry's biological father. Fanfiction allows for a lot of creative reinterpretation of the original story. Writers might do this to explore different character dynamics and add new layers of drama and relationships to the Harry Potter universe.
In some fanfictions, Snape is indeed portrayed as Harry Potter's father. Fanfiction allows for creative reinterpretations of the original story, and this is one such interesting deviation from the canon where Snape's complex relationship with Harry takes on a whole new dimension.
Yes, there might be. The world of fanfiction is vast and full of creative and unexpected ideas. Some authors like to play with the established relationships and characters' interests in unique ways. There could be a story where Harry's father has an odd admiration for Snape, perhaps seeing something in him that others don't. This could lead to all sorts of interesting plot twists and character interactions.
Yes, there are quite a few. Some explore how Snape's relationship with Harry would be different if he were his father. For example, in some fanfictions, Snape would be much more protective of Harry from the start, using his knowledge of the Dark Arts to shield Harry from threats that James Potter might not have been able to anticipate.
Yes, there are some out there. Some fanfictions explore this alternate relationship in really interesting ways. They might rewrite key scenes from the original series with this new family dynamic in mind. For example, Snape's interactions with Harry could be completely different, filled with a fatherly protectiveness that was hidden before. However, not all fans of the original series like this concept as it goes against the canon, but it does open up new and exciting storylines for those who enjoy exploring different possibilities.
One possible plotline could be Snape secretly protecting Hermione throughout her time at Hogwarts. He might give her special attention in Potions class, for example.
One consequence is a change in Harry's self - identity. He would have to reevaluate who he is in relation to Severus. Also, the relationship between Harry and the other characters, like James Potter (who was originally his father), would need to be reimagined.
There are many fanfictions that explore Severus Snape's father. Some might depict him as a cruel man who had a negative impact on Snape's childhood. In some fanfictions, he could be an absent figure, which might have contributed to Snape's rather solitary and often bitter nature.