Another plot could be that Wednesday discovers a hidden connection between her family's dark past and some of the ancient, forgotten magic in the Harry Potter universe. For example, her family might have had some interaction with a dark wizard in the past that has now led to a curse on Hogwarts. Harry and Wednesday then have to work together to break the curse. Wednesday's no - nonsense attitude and knowledge of the darker side of things could be a great asset in this adventure.
A fanfiction could be set in a world where Hogwarts has an exchange program with Nevermore Academy (Wednesday's school). Harry Potter is chosen to go to Nevermore, and Wednesday is sent to Hogwarts. At Hogwarts, Wednesday has to deal with the magical chaos and the rather more optimistic students compared to her own schoolmates. Meanwhile, Harry has to navigate the strange and often macabre world of Nevermore, and they both learn a lot from each other's worlds.
A great plot could be a duel between Harry and Wednesday. Harry uses his wizarding spells while Wednesday uses her unique skills of dealing with the spooky and unexpected. It would be a battle of two very different kinds of power. Another plot could be a quest where they both search for a lost magical artifact that has the power to bring out the darkest secrets of both their worlds. They have to overcome many obstacles together, like strange creatures and dark magic spells.
In a fanfiction, Wednesday Addams could visit Hogwarts. She would probably find the castle fascinating, but also a bit too cheery in some parts. She might make friends with some of the darker - themed students, like those from Slytherin. And she could introduce them to her pet spiders and other creepy - crawlies. Harry would be intrigued by her and her family's attitude towards death and the afterlife, which is different from what he has learned in the wizarding world.
First, you need to do your research on both universes. Know the characters well, their backgrounds, their personalities. For Harry Potter, understand the magic system, the Hogwarts houses, etc. For Wednesday Addams, know her family, her love for the macabre. Then, think of a creative way to bring them together. It could be a portal between their worlds or some sort of magical accident. When it comes to the 'lemon' part, build up the relationship gradually. Don't rush into it.
Well, a lemon fanfiction usually implies some sort of romantic or at least very close relationship scenario. In this case, combining Harry Potter and Wednesday Addams, it could be a wild and out - of - the - box story. Maybe it's about a crossover universe where Harry, with his magical world, meets Wednesday's dark and spooky world. And perhaps there's a strange attraction between them that defies the norms of their respective universes.
One idea could be that Shikamaru, with his strategic mind, gets transported to the wizarding world of Harry Potter. He could use his intelligence to help Harry and his friends in their battles against Voldemort. For example, he might come up with unique battle plans that the wizards hadn't considered before, like using the environment in Hogwarts in unexpected ways during duels.
One idea could be that Bilbo's ring somehow ends up in the wizarding world of Harry Potter. Maybe it's discovered by a Hogwarts student on an archaeological dig during a school trip. Another could be that Bilbo is brought forward in time to Harry's era and he uses his hobbit stealth and Tookish curiosity to explore Hogwarts and help the trio in their fight against Voldemort. For example, his experience with Smaug could give him insights on how to deal with dangerous magical creatures.
A more complex plot could be that a magical experiment at Hogwarts goes wrong and opens a portal to Albedo's world. Albedo and some of the Hogwarts students, like Harry, Ron, and Hermione, cross over into Albedo's world. There, they discover that the alchemy in Albedo's world has the potential to either save or destroy the magic in the Harry Potter world. So they have to work together, with Albedo teaching them about alchemy and the Hogwarts students teaching him about magic, to fix the situation before it's too late.
One plot idea could be that a Kitsune disguises itself as a student at Hogwarts to learn more about human magic. It could get involved in Harry's adventures and use its Kitsune abilities, like shape - shifting or illusion - casting, to help or sometimes cause trouble. Another idea is that a Kitsune is a guardian spirit of an ancient magical place near Hogwarts, and Harry discovers it during one of his explorations. The Kitsune then becomes an ally or a guide for Harry in uncovering secrets about the wizarding world.
One idea could be that a Lamia, a half - snake creature, secretly helps Harry Potter in the Forbidden Forest. Maybe she has unique knowledge of the forest's magic that can assist Harry in his quests.