It changes the story a great deal. First, the Mokuton gives him an edge in combat as he can manipulate plants and wood. This could be used in creative ways like creating huge forests to trap enemies or using wooden constructs for offense. The Rinnegan, on the other hand, is a whole new level of power. He could potentially use it to travel between dimensions, which would open up new plotlines. For example, he could discover new threats or allies in other dimensions. Overall, his character would become more complex as he tries to master these new powers.
His relationship with Sasuke would likely become more complex. Sasuke might be both jealous and intrigued by Naruto's new powers. Naruto would have to prove that he still values their friendship despite his increased strength. With Sakura, she might see Naruto in a new light, perhaps with a bit more admiration as he now has such rare and powerful abilities.
Regarding Kakashi, he would be both proud and a bit worried. Proud because Naruto has grown so much, but worried about how Naruto will handle such great power. Kakashi would offer more guidance and training, and their relationship would shift from mainly teacher - student to more of a partnership, with Kakashi acting as an advisor to Naruto on how to use his powers for the greater good.
If Naruto gains the Rinnegan in fanfiction, it could change the story in many ways. For one, his power level would skyrocket. He might be able to use all the abilities associated with the Rinnegan like the Six Paths techniques. This would make him an even more formidable opponent against enemies. Also, it could change his relationships. His friends might view him differently, either with more awe or perhaps some fear due to his new, extremely powerful ability.
With Mokuton, Naruto could grow trees instantly for various purposes like creating shelters or using them as weapons. And with Rinnegan, he might be able to use the Deva Path to control gravity, push or pull enemies. He could also use the Asura Path to create mechanical arms or other body parts for enhanced combat.
Well, it could make Naruto extremely powerful right from the start. With the Rinnegan, he might be able to master all types of jutsu more quickly. He could also have an edge in battles against powerful foes like Madara or Kaguya. Maybe he'd be able to use the six paths techniques with more ease and less training.
In a fanfiction where the Rinnegan is present during the Chunin Exams, it would have a massive impact. The Rinnegan's various paths offer different strategic options. The Asura Path could create extra limbs or weapons, which would be a huge shock to other examinees. This might also cause other characters like Naruto or Sasuke to view the wielder as a major threat. It could also lead to new alliances forming, as characters might try to either befriend or oppose the Rinnegan user.
Another possibility is that it's a result of some strange chakra experiment gone wrong (or right). Scientists in the Naruto universe are always dabbling in chakra research. Maybe an experiment meant to enhance her natural abilities instead gives her the Rinnegan, and she then has to learn to control it quickly to avoid being consumed by its power.
If Naruto got the Rinnegan in fanfiction, he would become even more OP (over - powered). His fighting style would be completely different. He could use the Preta Path to absorb chakra attacks, which means he could nullify a lot of his opponents' moves. This would make him a much more formidable foe. In terms of the plot, it might lead to new alliances and rivalries. Maybe some characters who were previously neutral would now see Naruto as a threat, while others would flock to his side to benefit from his new power.
It would be a wild change. Naruto's Rinnegan powers would make him a major force in the Fairy Tail world. He might be able to use the Preta Path to absorb magic attacks, which would be a huge advantage. And his Deva Path could manipulate gravity in ways that are unheard of in Fairy Tail. This could lead to new alliances or rivalries. Maybe some Fairy Tail members would be in awe of his power and want to learn from him, while others might be jealous or afraid.
Well, for one, he would become more self - assured. The Rinnegan is such a powerful dojutsu that it would change his perspective on his own strength. He'd see himself as more of a force to be reckoned with. And the Hyoton would force him to adapt his combat techniques. He might start training more in isolation as he tries to master these new powers. This would lead to a shift in his relationships too. He'd still care about his friends, but he'd be more independent in his growth journey.