Well, in this fanfiction idea, Naruto becoming Shao Kahn would be a wild transformation. Naruto is used to his world of ninjas and elemental jutsus, while Shao Kahn rules a dark and brutal realm. Maybe Naruto gets trapped in Shao Kahn's body due to a sorcerer's spell gone wrong. At first, he would be completely out of his element, but his adaptable nature would kick in. He would try to understand Shao Kahn's power and use it for good, like trying to end the constant bloodshed in Outworld and bring some peace, while also having to deal with the enemies that Shao Kahn has made over the years.
Naruto could adapt by using his strong willpower. He has faced many challenges in his own world, so he would rely on that experience. He might start by learning about Shao Kahn's powers and the politics of Outworld. His ability to make friends quickly could also help him. He could form alliances with some of the more reasonable characters in Outworld who were previously afraid of Shao Kahn.
One way it could work is by having a magical portal open between the Harry Potter universe and Shao Kahn's realm. Harry and his friends could be accidentally transported there. Then they'd have to use their magic to survive in a world full of Outworld's warriors. Maybe they'd teach some of the magic to the good - hearted people in Outworld and in return learn some of their combat skills.
First, research about Shao Kahn's character, his powers, his motives in the original Mortal Kombat universe. Then, choose the other element for the crossover. After that, think of a plot that would bring these two together in an interesting way. For instance, if it's a crossover with a sci - fi world, you could have Shao Kahn's portal technology malfunction and he ends up in a spaceship.
Perhaps in this fanfiction, Naruto discovers Shao Kahn's world and is in awe of his power. He then decides to study under Shao Kahn, or at least learn from his philosophy of power and domination. This could lead to Naruto facing a moral dilemma as Shao Kahn's values might conflict with his own ninja way. So he has to figure out how to adapt and still stay true to his friends and village.
The unique aspect is the clash of two very different universes. Naruto's world is full of ninjas, chakra, and honor - based battles. Shao Kahn's world is more about brute force and dark magic. When combined in fanfiction, it creates a really exciting mix.
One great 'Shao Kahn x OC Fanfiction' is 'The Kahn's New Ally'. It has an interesting plot where the OC is a powerful sorceress who catches Shao Kahn's eye. Their interactions are full of power dynamics and political intrigue within the Mortal Kombat universe.
Obviously Naruto would be one of the main characters as the title implies his connection to this fanfiction. And Shao Kahn would also be a main character since Naruto is his fan in this concept.