Perhaps there is a magical tournament in the wizarding world that is modeled after the jousts and challenges in King Arthur's court. Harry is forced to participate and as he does, he realizes that there are deeper connections between the values of the Arthurian era and the current state of the wizarding world. He then uses this knowledge to bring about positive change in the wizarding community.
One way could be through a prophecy. Similar to how there are prophecies in the Harry Potter series, there could be an ancient prophecy that ties Harry Potter to King Arthur. It could be that Harry has a role to play in restoring some of the lost magic or values of King Arthur's time, like chivalry and honor within the wizarding world.
One plotline could be that Hermione decides to start a new trend at Hogwarts by introducing muggle - style bikinis. She wants to break the traditional wizarding clothing norms and faces some resistance from the more conservative students and teachers at first, but eventually, it becomes a popular new style among the younger students.
One possible plotline could be that Harry discovers he has a hidden heritage related to the Dragon King. Maybe his parents had some connection to the Dragon King's world that was kept secret, and now he has to figure out how to use this new - found knowledge and power to fight against Voldemort.
A possible plotline could be that during an eclipse, Harry's glasses become a portal to another dimension within the wizarding world. He steps through and finds himself in a place where the rules of magic are different. Another plotline might involve the glasses being enchanted by an eclipse - influenced spell that causes Harry to see things that others can't, like hidden messages on Hogwarts' walls.
A simple plotline could be that Tony Stark, being the genius he is, discovers a way to enter the wizarding world. He meets Harry Potter and they exchange knowledge. Tony shows Harry some of his high - tech gadgets like the Iron Man suit, and Harry shows Tony some basic spells. They then team up to fight a new threat that emerges in the wizarding world that requires both magic and technology to defeat.
Another plot could involve Harry and Katniss being summoned to a parallel dimension where they are the only ones who can stop an ancient evil. They have to combine their unique skills, Harry's knowledge of magic and Katniss's survival and combat skills. They start off as strangers but gradually develop a deep friendship as they face numerous challenges together, like fighting off dark creatures and solving magical - mechanical puzzles.
One possible plotline could be that they are long - lost relatives from different magical or fantastical worlds. Maybe there's a prophecy that involves both of them.
One possible plotline could be that they are long - lost relatives through some ancient magic. Maybe a wizard from Harry's world once visited the Naruto world and had a family there. Another could be that they are connected by a prophecy that states they must join forces to defeat a great evil that threatens both their worlds.
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.
Well, one possible plotline could be a story where a character from the wizarding world, perhaps a powerful wizard, takes on a concubine in a parallel world or an alternate version of the wizarding society. The concubine might be from a different magical culture and their relationship could cause political or social unrest within the wizarding community.