In many fanfictions, the scenario of Naruto and Itachi killing the Uchiha clan is a very interesting but also controversial topic. One aspect could be the change in Naruto's character. Usually, Naruto stands for justice and protecting others. If he were involved in such a massacre, it would be a huge deviation from his original character. Maybe in the fanfiction, there could be some extreme situations that force him to do so, like being mind - controlled or having some false information.
In some fanfictions, a possible motivation for Naruto could be to prevent a greater evil. Maybe he was tricked into believing that the Uchiha clan was about to start a war that would destroy the entire ninja world. So, he thought that by taking part in killing the clan, he could save more lives in the long run.
In some fanfictions, Konan might use her origami techniques in a highly lethal way. Maybe she creates a large number of explosive paper bombs and traps Obito in a confined space, detonating them all at once to overpower his defenses and kill him.
One idea could be a story where Itachi and Kushina meet in a parallel universe. In this universe, the events of the original Naruto storyline are altered, and they end up on the same side, fighting against a new common enemy. Their unique abilities, Itachi's Sharingan and Kushina's powerful chakra, would make for an interesting combination in battles.
Let's imagine Itachi Uchiha in love with a fellow Uchiha. They grew up together, trained together. Their love was based on a deep understanding of each other's pain and power. But when the Uchiha clan's fate was at stake, Itachi had to make difficult choices. His love for her was strong, but his loyalty to the village made him do things that seemed to shatter their relationship. In the end, his love remained in his heart, a hidden and painful memory.
One common theme is redemption. Since Obito has done a lot of bad things in the Naruto series, many fanfics focus on him trying to make up for his mistakes. Another theme is love, whether it's his love for Rin that drives his actions or new relationships he forms.
A different fanfiction could involve a magical experiment gone wrong that transports Harry Potter to the Naruto world where he meets Obito. Harry, with his knowledge of magic, and Obito, with his ninja skills, have to find a way back to their respective worlds. Along the way, they learn from each other's cultures and abilities. Harry could teach Obito about some basic spells, and Obito could show Harry some ninja techniques like how to move stealthily or use a kunai effectively.
One great Obito Uchiha time travel fanfiction is 'A New Chance for Obito'. In this story, Obito travels back in time and tries to prevent the tragedies that befell the Uchiha clan. It's really engaging as it shows his internal struggle to change things while not disrupting the entire timeline too much.
There's also 'Obito's Unlikely Bond'. In this fanfic, the OC is a healer who stumbles upon a wounded Obito. Their relationship starts off rocky but gradually turns into something deeper. The story does a wonderful job of exploring Obito's complex emotions and how the OC helps him come to terms with his past. It's a really heartwarming read.
Yes, there might be. There are many creative fanfiction writers in the world who like to combine different fictional universes. Some might have come up with the idea of integrating Harry Potter and Obito Uchiha. You can try searching on popular fanfiction websites like Fanfiction.net or Archive of Our Own to see if there are any such stories.