If Naruto has Obito's eyes in fanfiction, his abilities would be enhanced in several ways. The Sharingan's ability to see chakra flow clearly would allow Naruto to better analyze his opponents' moves and weaknesses. With Kamui, he could teleport himself or objects, which would be a huge advantage in battles. He might also be able to use some of the more advanced Sharingan - related genjutsu, adding another layer to his combat skills.
One plot implication could be that Naruto is initially distrusted by some in the village. They might see the Sharingan as a symbol of danger or the Uchiha's past misdeeds. This could create internal conflict within the village. Also, Naruto might be hunted by enemies who fear the power of the Sharingan in his hands.
Their friendship in fanfiction could be really interesting. Maybe they start as rivals but then realize they have a common goal. For example, protecting the Hidden Leaf. They could learn from each other's jutsu. Naruto could learn about space - time ninjutsu from Obito while Obito could learn about Naruto's positive attitude towards life.
Obito's influence would likely make Naruto more aware of the darker side of the ninja world. Naruto is usually very optimistic, but with Obito's guidance, he would see the hardships and betrayals that can happen. For example, Naruto might become more cautious in his trust of others.
In some fanfictions, it might be so. Fanfiction allows for creative and often out - of - canon interpretations. However, in the original Naruto series, Naruto has no relation to Obito in this way.
Typically, he would have the Sharingan in his eyes. So, instead of his normal blue eyes, one or both of his eyes would have the characteristic red with the tomoe pattern of the Sharingan. It gives him a more menacing look, which is quite a contrast to his usual friendly appearance.
One possible fanfiction could be about Naruto and Obito teaming up to face a new, powerful enemy. They could combine their unique skills, like Naruto's Rasengan and Obito's Kamui. Their relationship could start off rocky due to their past differences but gradually turn into a strong bond as they fight side by side.
In some stories, the fox eyes might give Naruto a kind of hypnotic or intimidating power. Enemies might be momentarily stunned or less able to fight effectively when they look into his fox eyes. This could be a unique advantage in battles, allowing Naruto to gain the upper hand without having to use as much physical force.
His relationships with his friends might become stronger. Since he can see more clearly with his god eyes, he can better protect them. His friends would trust him more knowing he has this extra power to keep them safe.
One great fanfiction is 'The Fox - Eyed Naruto' on FanFiction.net. It really delves into how Naruto's fox - eyed appearance changes the way people perceive him in the village. The author does an amazing job of integrating this new physical trait into the existing Naruto universe storyline.