Well, Naruto getting Madara's Sharingan in a fanfic would be wild. First off, the Sharingan could potentially enhance Naruto's combat awareness even more. He might be able to see through genjutsu easier, not just because of his own chakra but also the Sharingan's anti - genjutsu capabilities. Also, it could open up new story arcs where Naruto has to learn to control the Sharingan's powers, which are quite different from his normal ninja skills.
It could have a huge impact on the balance of power in the ninja world. With Naruto having Madara's Sharingan, other villages might become more cautious or even hostile towards Konoha. This would lead to new political situations and alliances. Moreover, Naruto's training and growth would take a new direction. He would need to learn how to combine his existing abilities with the new powers of the Sharingan, which would be a complex and interesting process to explore in the fanfiction.
One possible fanfiction could be about a young ninja who discovers he has a special connection to Madara's Sharingan. Maybe he inherits some of Madara's latent powers through a mysterious family link. This could lead to him being hunted by those who want to use his power for evil or by those who fear it.
The plot could change drastically. For one, the power balance in the ninja world would be severely disrupted. Enemies that were once a threat would be easily dealt with. The fusion could also change the political situation. With its combined charisma (from Naruto) and intimidating presence (from Madara), it could unite or divide the villages depending on its goals.
In fanfiction, it could be due to a strange encounter with a magical or ancient artifact. This artifact has the power to transfer the Sharingan's essence from Madara to Naruto. It might be a relic from an ancient battle between the Uchiha and some other powerful force, and when Naruto and Madara come into contact with it, the transfer occurs.
Well, in this fanfiction, Madara could give Naruto the Sharingan as a way to balance the power in the ninja world. Naruto then uses the Sharingan's ability to predict movements in combat. This gives him an edge against enemies who are used to his regular fighting style. He might also discover some hidden abilities of the Sharingan that no one else knew. For example, it could have a unique connection to his Nine - Tails chakra, creating a whole new set of jutsus.
If Naruto becomes Madara Uchiha in fanfiction, it could drastically change the plot. Firstly, the relationships would be turned upside down. Naruto's friends might see him as an enemy, especially Sasuke who has a complex relationship with the Uchiha legacy. The power dynamics in the ninja world would also shift. Naruto, with Madara's power and knowledge, could either rule with an iron fist or try to reshape the world in a more extreme way compared to his original goal of peace. And the Akatsuki's plans would likely be disrupted as Naruto, in Madara's form, might have different motives regarding the tailed beasts.
In some fanfictions, it could be through a divine intervention by Kami. Maybe Kami sees Naruto's pure heart and his need for more power to protect the village. So, Kami decides to bestow upon Naruto the power of Madara's Sharingan as a way to give him an edge in battles against powerful foes.
Naruto with Shisui's Sharingan would have some amazing new abilities. The Sharingan's visual prowess would let Naruto see chakra flow more clearly. This means he could detect hidden enemies or traps more easily. In terms of his existing skills, his Rasengan could be enhanced. He might be able to infuse the Sharingan's power into it, making it even more destructive. Also, his teamwork with his friends would be different. He could use the Sharingan to better coordinate with them during joint missions. For instance, he could quickly assess the situation and direct his friends to the best positions in a battle.
Well, if Naruto was born with the Sharingan, it would completely disrupt the original power dynamics. He'd have an edge in combat from the start. For example, he could quickly copy jutsu like Sasuke does with his Sharingan. This might make his early training with Iruka and Kakashi very different as he'd already have a powerful dojutsu at his disposal.
If Naruto kills Madara in fanfiction, it could completely shift the power dynamics in the Naruto universe. For one, it might lead to a more peaceful era much sooner as Madara was a major source of conflict. The Akatsuki's plans would likely fall apart without his influence, and the shinobi villages might start to focus more on internal rebuilding and cooperation rather than external threats.