There could be an interesting plot where the queen, aware of Harry's fame and abilities, enlists his help to solve a long - standing mystery in the royal family. This mystery could be related to some ancient curse or a hidden treasure that has magical properties. Harry, along with his friends from Hogwarts, embarks on a journey to uncover the truth and protect the queen's interests. Or perhaps, the wizarding world and the Muggle world, represented by the queen, need to form an alliance due to a new and powerful dark force emerging. Harry is the bridge between the two worlds and has to ensure the cooperation runs smoothly while serving the queen's needs.
In some fanfictions, the Queen might be a long - lost relative of a pure - blood wizarding family. This would lead to her being involved in the complex politics of the wizarding world. She could use her position as the Queen to try and bring about change in the wizarding world's old - fashioned pure - blood - supremacy - based society.
It's not a very common or mainstream genre. Most Harry Potter fanfiction focuses on the wizarding world's own lore, characters' relationships, and adventures within that magical realm rather than this specific concept of serving the queen.
Well, in a 'fem Harry is a Queen fanfiction', a plotline could be that fem Harry dreams of Queen and in her dreams, the band members give her advice on how to deal with Voldemort. This then gives her the strength and new strategies to fight against the dark forces. Also, it could be that she discovers a hidden connection between Queen's music and ancient magic that only she can unlock, leading to her becoming a more powerful witch.
One plotline could be Naruto being a transfer student at Hogwarts. He might struggle to adapt to the magic system while also showing off his ninja skills. Another could be Naruto teaming up with Harry Potter to fight a common enemy that threatens both the ninja world and the wizarding world.
One possible plotline could be Harry using his knowledge of the wizarding laws, which he learned through his years at Hogwarts and his experiences with the Ministry of Magic, to defend wrongly accused wizards in a wizarding court. Another could be him trying to reform the wizarding legal system which he might find full of loopholes and biases.
One possible plotline could be Harry trying to hide his merman identity while at Hogwarts. He might face challenges in the magical underwater areas of the school, like the lake. Another could be that he discovers his merman heritage and has to go on a journey to learn more about it and his new powers.
One possible plotline could be Harry being secretly trained by an unknown figure to become an assassin against the dark forces. He would have to hide this new identity from his friends at Hogwarts.
One possible plotline could be about the Weasley family trying to improve their financial situation. Maybe they come up with a new business idea in the wizarding world, like a magical product that becomes a huge success and changes their economic status. Another could be a story about how the Ministry of Magic regulates the financial system in the wizarding world, and there are some characters who try to manipulate or reform it.
One possible plotline could be a Lannister student at Hogwarts. They might bring their family's ambition and power - hungry nature into the school, causing all sorts of drama among the houses. For example, trying to take over the Slytherin house leadership through manipulation.
A possible plotline could be that Harry uses his invisibility to spy on Voldemort's followers and gather intelligence for the Order of the Phoenix. This would add an element of mystery and danger as he has to be extremely careful not to be detected.