Well, perhaps a fanfiction where the Sorting Hat from Harry Potter is brought into the FFXV world. The characters in FFXV are sorted into Hogwarts houses based on their personalities. Noctis could be in Gryffindor for his courage, Prompto in Hufflepuff for his loyalty. And then there could be a quest to find a way to send the hat back, all while dealing with the usual threats in the FFXV world like daemons.
A possible plot for Harry Potter FFXV fanfiction is that the Death Eaters somehow make a pact with the empire in FFXV. This forces the heroes from both universes to join forces. Harry and Noctis could learn from each other's combat styles and magical abilities. The wizards could teach the FFXV characters about spells like Apparition, while the FFXV characters could show the wizards how to use their unique weapons and summons in combat.
I think Luna Lovegood and Prompto would make a really fun pairing. Luna has her unique and somewhat otherworldly view of things, and Prompto is the cheerful and energetic one in the FFXV group. They could have some really interesting conversations about the strange creatures in both their worlds. Also, Severus Snape and Gladio could be an unexpected but fascinating pairing. Snape's dark and brooding nature contrasted with Gladio's tough and protective side.
Maybe there could be a story where the Keyblade wielders from Kingdom Hearts visit the world of FFXV to learn about their unique form of magic. They could then exchange knowledge, like how Noctis' warp strikes could be adapted into a new Keyblade ability.
One idea could be creating an OC who is a powerful mage from a long - lost clan. They could join the main characters on their journey and use their unique magic to help in battles and solve problems. For example, they might have the ability to control time briefly, which could be crucial in a tough fight against a powerful daemon.
A great plot for a Potter Manor fanfiction could involve a mystery that surrounds the manor. For instance, strange noises at night lead Harry to uncover a long - forgotten chamber. It could also be about Harry restoring the manor to its former glory, perhaps with the help of Hermione's research on ancient magic used in the construction of such manors.
One interesting plot idea could be exploring what would happen if Harry had a different upbringing, like being raised by the Malfoys. It would completely change his view of the wizarding world and his relationships. Another idea might be a time - travel fanfic where Harry goes back to the Marauders' era and interacts with his parents and their friends. This could lead to him preventing certain tragedies or changing the future in unexpected ways. And then there's the concept of a fanfic where the roles are reversed, and Voldemort is the one trying to protect the wizarding world from a greater evil, with Harry being the main antagonist.
One idea could be Harry Potter using his wizard skills in a boxing ring in a unique way. For example, he might use a levitation charm to dodge punches or use a stunning spell on his opponent's gloves to make them heavier. Another could be a story where the wizarding world has its own boxing league and Harry has to compete against other magical beings like werewolves or giants in the ring.
An enchanter in a fanfiction could create a spell that allows them to communicate with portraits in a way that has never been done before. For example, they could get advice from portraits of long - dead headmasters on how to deal with the current political situation in the wizarding world. Another plot might be that an enchanter is able to enchant the Sorting Hat to sort students based on their future potential rather than their current characteristics. This could lead to some students being placed in houses that they never expected. And finally, an enchanter could be working on a spell to make the Hogwarts Express invisible during its journey, but things go wrong and the train starts to disappear and reappear at random intervals, causing panic among the students.
One idea could be that Amara is a new student at Hogwarts with a special power to communicate with magical creatures in a way no one else can. Harry discovers this and they team up to solve a mystery involving a group of sickly unicorns in the Forbidden Forest.
One idea could be a wedding between a wizard from Gryffindor and a witch from Slytherin, which could cause a stir among the Hogwarts alumni. They might have to overcome the old prejudices of their houses. Another could be a wedding set during a time of peace after the battle of Hogwarts, with characters like Harry and Ginny as guests, and the wedding could incorporate a lot of traditional wizarding wedding elements like flying doves made of light magic.
One idea could be that Lelouch, with his strategic mind, somehow gets transported to the Harry Potter world. He could use his Geass ability in a very different way, like influencing Death Eaters to turn against Voldemort. Another could be Harry Potter and Lelouch teaming up to fight a common enemy that has elements of both their worlds, perhaps a dark wizard who has also mastered some form of mind - control magic similar to Geass.