Yes, there are likely to be such fanfictions out there. The Harry Potter and Pokemon universes are both extremely popular, and fans often like to combine different fictional worlds in fanfiction. You can try searching on fanfiction websites like Archive of Our Own or FanFiction.net.
The legendary wands in Harry Potter are full of mystery. In fanfiction, a story could be about a wandmaker who tries to recreate the Elder Wand. He might study all the old texts and legends, but in the process, he discovers a dark secret about the wand - making process that was long forgotten. This could lead to a battle between good and evil, with the fate of the wizarding world at stake.
A fanfiction might focus on the relationship between a wizard and his or her legendary wand. For example, Harry's connection with the Elder Wand could be explored further. What if the wand had a hidden power that only manifested when Harry was in a life - or - death situation? This could add a new layer to the story, showing how the wand and the wizard are truly intertwined and how their bond can grow and change over time.
I'm not sure specifically as there could be many different interpretations in fanfics. Generally, it might involve Harry Potter discovering he is the heir to some great and legendary fortunes, which could lead to new adventures, encounters with previously unknown magical elements or families, and a whole new set of challenges as he tries to understand and claim this inheritance.
Well, in some fanfictions, the legendary sword might be enchanted with special powers like being able to cut through any dark magic. It could also have a mind of its own and only allow Harry to wield it when he's in a pure - hearted state.
Obviously, Harry Potter would be one of the main characters. Since it's about him being the heir. Hermione and Ron are likely to be important too as they are always by Harry's side in most of his adventures.
One challenge is keeping the integrity of both universes. For instance, the magic in Harry Potter is very different from the powers of Pokemon. So, it's difficult to make sure that when they interact, it doesn't seem forced. Another challenge is the different fan bases. Some die - hard Harry Potter fans might not like the idea of mixing it with Pokemon, and vice versa.
Hermione would be a great helper. She's super smart and has a vast knowledge of magic. She could research ancient spells and magical materials needed for the weapon. Ron could also be involved. He's brave and has a lot of practical experience in dealing with magical situations. His loyalty would make him a reliable partner in the weapon - making process.
As I mentioned before, Archive of Our Own (AO3) and FanFiction.net are good places to start. Just use the search bar on those sites and type in relevant keywords like 'Harry Potter', 'legendary Pokemon', and 'fanfiction'. There may also be some smaller, more specialized fanfiction communities that might have such stories, but those two are the most well - known and likely to have a wide selection.