Another character that could be involved is Odin from the Marvel side. He might have his own thoughts about this 'Loki' (Harry) and his actions. On the Harry Potter side, Dumbledore could make an appearance in a more magical - realm - overlapping scenario. Dumbledore might be able to sense that something is amiss and try to help Harry navigate this identity crisis in a world that is not his own.
The Avengers could be involved. Captain America, for instance, might be suspicious of this 'Loki' (who is actually Harry) and keep a close eye on him. Iron Man could use his technology to analyze Harry, thinking he is Loki. And from the Harry Potter universe, Ron could be there, trying to support Harry in this strange situation where he is mistaken for someone else entirely.
If Harry Potter is mistaken for Loki fanfiction, there would be a huge clash of universes. Fans of both might be either outraged or find it oddly interesting. For one, the magic systems are completely different. Harry Potter's magic is more about spells and potions, while Loki's is more of a godly, illusory kind. It would be a mess of expectations and interpretations.
There could also be new characters introduced. Maybe other magizoologists from different parts of the wizarding world. They could have different approaches and beliefs about magical creatures. Some might be rivals, trying to outdo Harry in the discovery and study of new species, while others could be mentors, guiding him in the complex world of magizoology.
The Weasley twins could be part of it too. Suppose Harry yells in excitement or anger about a new prank idea that the twins have come up with that might be a bit too dangerous. They could either encourage his yelling or try to tone it down, depending on their mood. And Malfoy might overhear Harry's yell and use it as an opportunity to taunt him, adding more conflict to the fanfiction.
Well, in this type of fanfiction, Hermione could also be an important character, but in a different light. Maybe she tries to stop an evil Harry, or perhaps she is corrupted by him and becomes his accomplice. Other characters like the White Witch from Narnia could be involved. Her icy magic and cold - hearted nature could be an interesting contrast or complement to an evil Harry's powers. And don't forget about characters from other YA dark fantasy series, such as the Darkling from Shadow and Bone, who could potentially cross paths with an evil Harry.
On the Hogwarts side, Hermione and Ron would surely be there. They could be quite bewildered by Harry's newfound connection to Olympus. And Dumbledore, he might have some knowledge about the connection between the two worlds and could guide Harry in some way. From the Olympus side, Athena could also be involved as she is the goddess of wisdom and might see potential in Harry.
Obviously, Harry Potter himself. Then there could be Hermione and Ron, who would be his friends and help him deal with the revelations of his parentage. Dumbledore would also be there, guiding Harry as he tries to understand his connection to Ariel. And perhaps some sea - based characters like mermaids or sea wizards who come to Hogwarts to interact with Harry.
Dumbledore could make an appearance. He might be the one who gives Harry the idea to become a pilot in the first place or provides some ancient magical knowledge about flying that helps Harry in his new career. Also, the Weasley twins could be involved. They could create some magical gadgets for the plane, like a device that makes the plane do cool stunts.
One plot idea could be that in a magical realm where different fictional universes collide, Harry's appearance or some magical mishap makes others think he is Loki. Maybe the characters from the Thor/Loki universe initially treat him as Loki and he has to figure out how to convince them otherwise while also dealing with the chaos that ensues. For example, he could be caught in the middle of a power struggle between Thor and those who believe he is Loki up to no good.
Ron could also be there. He would be the more practical one, gathering resources like food and water for Harry during the pregnancy and labor. He might also be the one to keep Harry's spirits up when the situation seems dire.
Well, Hulk could be involved in a more physical sense of bullying. His uncontrollable rage might be directed at Loki in the fanfictions. Black Widow, with her skills in manipulation, could also play a part in making Loki's life difficult. Hawkeye, being a loyal member of the Avengers, might follow the group's lead and be part of the bullying, perhaps using his archery skills to intimidate Loki.