There might be. In the Naruto series, both Naruto and Nagato have complex backstories. If they were brothers in a fanfic, it would be really interesting. Maybe Naruto could have influenced Nagato to take a different path earlier. For example, Naruto's positive attitude towards life and his belief in peace could have rubbed off on Nagato, preventing him from going down the more violent routes he took in the original story.
In some fanfictions, Naruto and Nagato might be related through their shared experiences with the ninja world. They both faced great tragedies. Naruto could be seen as a successor to Nagato's ideals in a way. Nagato once wanted peace through force, but Naruto shows that peace can be achieved through understanding and forgiveness.
Naruto could also be a bit angry at first. Angry that she had been away from him all this time. But then that anger would quickly turn into overwhelming love and relief. He would have so many questions to ask her about why she wasn't there as he was growing up, but at the same time, he would be so glad to have her there now.
One plot implication could be that Naruto becomes a target for more powerful enemies. Since the Rinnegan is such a powerful and coveted dojutsu, many villains might want to either steal it from him or kill him to prevent him from using it. Another aspect could be that Naruto has to learn to control the Rinnegan's powers, which could lead to some internal struggles as he tries to balance his existing powers with this new and extremely potent ability.
It would change his abilities in multiple ways. Firstly, with the Rinnegan, Naruto could have better perception of the world around him, similar to how Nagato was able to sense things from afar. Secondly, he might be able to use the Animal Path to summon powerful creatures. This would give him more options in battle. Also, the Rinnegan could potentially allow Naruto to access some form of chakra absorption or manipulation that he didn't have before, further diversifying his power set.
One possibility is that there was some sort of spiritual or chakra - based connection between Naruto and Nagato. Nagato, being the possessor of the Rinnegan, recognized Naruto's strong will and the fact that he was on a path to change the ninja world for the better. Through this connection, Nagato was able to transfer the power of the Rinnegan to Naruto. It could also be related to the nature of the Sage of Six Paths' power that was somehow involved in this transfer, as both Naruto and Nagato were related to the Sage in different ways.
In some fanfiction concepts, there could be a spiritual or mental connection established between Naruto and Nagato. Since Naruto has this unique ability to understand and connect with people on a deep level. Through this connection, Nagato might pass on the power of the Rinnegan to Naruto. It could be like a transfer of not just the physical power but also the knowledge and understanding that comes with the Rinnegan.
There were novels similar to Naruto: My Twin Brother Is Nagato:
1:" In Naruto, the Tranquil Court ", author: 71L
2." One Piece: I've Become Brother Ming's Brother ". Author: The Author Who Wants a Cigarette
3. Naruto: My Avatar is a Red Dog General. Author: Love Hot Pot
The following is a detailed introduction of these novels:
1." In Naruto, the Tranquil Court ": Zhong Cang accidentally passed through the Naruto World.
When he woke up, he was in Muye.
With a sword in his head, he became a special death god.
When he learned that he could summon the Death God of the Corpse Soul Realm to the Ninja Realm, change the ninja class to the Death God, and even resurrect the souls of the dead experts of the Ninja Realm as the Death God, he was shocked.
Zhong Cang began to hide behind the scenes of Ninja Realm as a joke.
…………
When the fourth generation couple resurrected, they learned about Naruto's encounter.
" Orochimaru," said Uzumakushina," when are you going to start your plan to destroy the wooden leaf?"
…………
When Naruto met the man in the white haori, he was shocked.
" Naruto, do you know the difference between a king and a mount?" A strange voice sounded in his head.
…………
" Okoteki, you don't want Kato Matsuki and Rope Tree to be bullied in the world of the dead, do you?"
Mu Ye: " Not good! Lord Fifth Generation Eye Huoying has defected!!"
…………
Under Zhong Cang's intentional indulgence, Black Jue finally revived the big cylinder wood Hui Ye, but he didn't have time to be happy.
A figure sat high in the sky and laughed softly.
"Welcome to my Corpse Soul World!"
Standing on the left and right, a group of figures wearing white feathers stepped forward.
They pulled out their swords from their waists.
"Unravel!"
2." One Piece: I Become Brother Ming ": Staying up late to work overtime and suddenly dying, only to wake up as the younger brother of Dominguez.
The Heavenly Dragon person who lost his noble status and was killed by the commoners.
The one who witnessed her brother killing her father and was adopted by the warring states.
The one who saved the God's Predator…
Don Quijote Rossinandi, who betrayed his brother!
"My stupid brother, is this all you can do?" Looking down at the man who was being stepped on, Rocinandi mocked calmly.
3." Naruto: My Clone is a Red Hound General ":" Double Penetration "," Invincible Cool "," Hot Blood "
A soul with a dual personality transmigrated to the Naruto World and the Pirate World.
They became the dying Zhi Shui and the Major General Chi Quan.
Not only that, but there was also some kind of connection between the two personalities.
When the red dog could use the Instant Body Technique, Chakra, immortal techniques…
When Zhishui could turn his body into elements, Tricolor Domination, Six Forms of Navy…
Several years later…
During the war, the red dog drove the Susanoku Gundam and joined the battlefield. At that moment, the red dog's reputation was even greater than the red hair's reputation.
When he faced Pei En, Zhi Shui fought six times and broke free from the restraints of the Earth-shattering Heavenly Stars.
You can read these novels on Qidian Chinese Network.
One possible plot could be that they grow up together in a small village. Naruto's positive influence makes Nagato less likely to be influenced by Madara's ideas later. They both train under Jiraiya, and together they try to bring peace to the ninja world in a different way than in the original story.
In these fanfics, Nagato may help Naruto on an ideological level. Nagato once believed in a very different way of achieving peace. By sharing his journey and how he came to realize the flaws in his thinking, he can guide Naruto in his pursuit of true peace. Nagato could also use his influence over the Akatsuki remnants to prevent them from causing more chaos, which in turn helps Naruto in his mission to protect the ninja world.