Well, he could be a foreign exchange student of sorts from a hidden land of ninjas. His skills would make him stand out immediately. He might befriend Harry and help him train in a different way of combat, using his Sharingan to analyze the weaknesses of their enemies like Death Eaters.
Itachi could be a part of a secret organization in the wizarding world that is dedicated to protecting a powerful magical artifact. His stealth and combat skills would be highly valuable in this role. And his Sharingan could be used to detect any hidden threats or magical traps around the artifact.
He could be in Slytherin. His cunning and ability to manipulate situations in the Naruto series could be seen as Slytherin traits. He was always thinking several steps ahead, just like many Slytherins are known for their strategic minds.
Sasuke could be a foreign exchange student of sorts. His Sharingan might be seen as a very rare and powerful magical ability. He would likely be very good at Defense Against the Dark Arts due to his combat skills.
Sure. There are often crossovers in fanfiction. Writers like to combine different beloved fictional characters. For the 'Harry Potter is Itachi Uchiha' idea, it could be really interesting. For example, Itachi's Sharingan abilities could be compared or integrated with magic in the Harry Potter universe. It might be a bit of a stretch in terms of the two very different settings, but that's the beauty of fanfiction. You can find such fanfictions on websites like Archive of Our Own or FanFiction.net if they exist.
Madara's Sharingan would be a very unique ability in the Harry Potter world. It could be used for things like detecting lies, seeing through invisibility spells that are not as advanced as the Sharingan's capabilities, and predicting an opponent's moves in duels. His ability to use fire - based jutsu could be seen as a form of very powerful and different magic. Also, his physical combat skills would make him a formidable opponent in a world where most rely on wands for combat.
Another concept could be a story where the magic in the Harry Potter world and Itachi's ninjutsu are somehow combined. Imagine Itachi using his fire - style jutsu along with a spell from the Harry Potter world to create a unique and powerful attack. This could be used against a common enemy that threatens both the ninja world and the wizarding world.
The Hulk could fit in as a powerful protector. His super strength can be a great asset against dark wizards. For example, when the Death Eaters attack, the Hulk could easily overpower them.
She could be a visiting expert from another magical realm. Her skills with plants would make her a valuable asset at Hogwarts, perhaps helping Madam Pomfrey in the hospital wing with plant - based remedies.
A nekomata could fit in as a rare and powerful familiar. It could be from a far - off magical land and brought to Hogwarts by accident or on purpose. For example, it might have been smuggled in by a dark wizard initially but then escapes and finds Harry.
He would likely be adapted as a very powerful and mysterious character. His skills in the Naruto universe would translate into some sort of special magical abilities in the Harry Potter world. For example, his Sharingan could be like a super - powerful magical eye that gives him unique insights.
There might be some very creative and out - of - the - box fanfictions out there that could have such a plot. However, it's quite an unusual crossover as 'Harry Potter' and 'Naruto' (where Itachi Uchiha is from) are two very different fictional universes. I haven't personally come across one, but with the vastness of the fanfiction world, it's possible.