One interesting storyline could be Naruto using the Sharingan to enhance his combat skills in a new and unexpected way. For example, he might combine his Rasengan with Sharingan - powered genjutsu to create a more powerful and deceptive attack.
Well, it changes a lot. For one, Naruto's power level gets a significant boost. Instead of relying solely on his Uzumaki chakra and Sage Mode, he now has the Sharingan's abilities like predicting movements and using genjutsu. This can make battles he's in much more complex and unpredictable.
One possible plot twist could be that Naruto struggles to control the Sharingan at first. Since he's not from the Uchiha clan, the Sharingan's powers might act differently in him. For example, instead of the normal abilities like predicting movements, it might give him visions related to the Uchiha's past traumas. This could lead to Naruto having to deal with not only the power of the Sharingan but also the emotional baggage that comes with it.
His relationship with Sasuke would become really complex. Sasuke, as an Uchiha, might feel a mix of jealousy and concern. Jealousy because Naruto now has a part of what makes the Uchiha special, and concern because he knows the dangers of the Sharingan. They might have more intense battles or training sessions as Sasuke tries to understand how Naruto got the Sharingan and how it's affecting him.
One possible plot twist could be that Naruto's new Mangekyou Sharingan gives him the ability to access a new form of Sage Mode. Since the Sharingan has unique powers and Sage Mode is Naruto's own power, their combination might create something unexpected. For example, he could use the Sharingan to better target his Sage chakra, making his attacks more precise and powerful.
His powers would change a great deal. Naruto is known for his brute strength and his ability to never give up. The Sharingan would add a whole new layer of finesse to his fighting style. He could use the Sharingan's genjutsu capabilities to trap his enemies in illusions before hitting them with a powerful chakra - infused punch. Also, he could use it to analyze his opponents' weaknesses more quickly, allowing him to adapt his fighting strategy on the fly.
With Sasuke, their relationship would become more complex. Sasuke might be both jealous and intrigued by Naruto having the Mangekyou Sharingan. Jealous because it was always an Uchiha thing, and intrigued because he wonders how Naruto will use it. This could lead to more intense rivalries and also more opportunities for them to understand each other better.
Another idea is a crossover with a superhero universe. Imagine a character like Sasuke with his Mangekyou Sharingan powers suddenly in the Marvel or DC universe. He could team up with heroes like Spider - Man or Batman. His Sharingan's ability to copy moves could be really interesting when facing off against super - villains.
It would change his relationships a lot. His friends like Sakura and Sasuke would be both intrigued and maybe a bit worried. Sasuke, who has his own Sharingan, might see Naruto as more of a rival now. Sakura would be concerned about the risks of the implantation. And his relationship with Kakashi would also shift. Kakashi could help Naruto better understand and control the Sharingan, creating a stronger bond between them as teacher and student.
One possibility could be a story where the power of the Sharingan from Naruto is introduced into the Avatar world where Azula exists. Maybe a character with Sharingan ends up in the Fire Nation and has to face off against Azula. This could lead to some really interesting battles and power dynamics as the Sharingan's abilities like seeing chakra flow and predicting movements would be new and challenging for Azula and her firebending skills.