He could have the ability to see chakra flow in extreme detail. This would allow him to not only detect enemies from afar but also predict their moves based on how their chakra is moving. He could also potentially have enhanced vision in non - combat situations, like being able to see in the dark much better.
Naruto could develop a new form of Rasengan that incorporates the Byakugan's ability to see chakra points. He could target an opponent's chakra points more precisely while using the Rasengan, making it a much more deadly attack. Also, he might be able to use the Byakugan to create illusions. By manipulating the chakra he sees with the Byakugan, he could create false images to deceive his enemies.
One new ability could be the long - range detection of large - scale chakra events. For example, he could sense when a powerful jutsu is being prepared in a far - off location. He could also combine the Byakugan with his shadow clone technique. His clones could relay visual information back to him, and he could use his Byakugan to analyze it all at once. This would give him a huge strategic advantage in battles and in gathering intelligence.
A character with Byakugan in such a fanfiction could have the ability to combine the Byakugan's vision powers with Fairy Tail's magic. For instance, they could use their long - range vision to aim long - distance magic attacks more precisely. They might also be able to detect hidden magical traps or passages that are invisible to the normal eye, just like they can detect hidden chakra in Naruto.
He could have the ability to use all six paths techniques right from the start. This means he could manipulate gravity like the Deva Path, absorb chakra like the Preta Path, and even revive the dead like the Outer Path.
He could develop the ability to combine the power of the Sharingan with the Nine - Tails' chakra. Maybe he could use the Sharingan to better control the Nine - Tails' power, for instance, seeing the flow of the chakra inside him more clearly. This could lead to new jutsu that are a fusion of Uchiha and Uzumaki techniques.
With the Sharingan and Byakugan, Naruto could come up with a new jutsu that involves the Sharingan's ability to predict an opponent's moves and the Byakugan's all - seeing vision. He could create a sort of 'preemptive defense jutsu' where he can sense an attack coming from any direction (thanks to the Byakugan) and then use the Sharingan's prediction to not only dodge but also counter - attack in the most effective way. Additionally, he might develop a jutsu that uses the unique chakra patterns seen by the Byakugan to disrupt an enemy's chakra system while using the Sharingan to keep the enemy locked in a genjutsu - like state, preventing them from escaping the chakra disruption.
One way could be through some kind of special experiment or ritual. Maybe a scientist in the Hidden Leaf Village discovers a way to transfer the Byakugan's power to Naruto. Another possibility is that he could inherit it in a very unique way, like through a spiritual connection with a Hyuga ancestor.
He could develop the ability to counter - attack more effectively. Since he can see the future, he would know exactly when and where an enemy will strike. This could lead to him developing a new fighting style that focuses on preemptive strikes and perfect defenses.
He could have the ability to use Sonido, which is a high - speed movement technique in the Arrancar world. This would make him much faster than normal ninjas. Also, his zanpakuto could have unique abilities, like the ability to cut through space - time, which would be a huge advantage in battles.
In this fanfiction concept, Naruto's new abilities could be vast. He might be able to access a new form that combines the features of all the Bijuus he houses. This form could have multiple tails, each representing a different Bijuu, and with each tail comes a different power. For instance, one tail could give him the ability to control water like the Three - Tails, while another could grant him the power of fire like some of the other Bijuus. He could also develop the ability to share the power of the Bijuus with his allies in a limited way, making his team even more formidable in battle.
The story would be altered significantly. Naruto being born with the Byakugan would mean that he could potentially master it at a very young age. This would give him an edge in the Academy. He could outperform his classmates in terms of perception and combat skills related to the Byakugan. His relationship with Sasuke might also be different. Sasuke, who comes from the Uchiha clan with their Sharingan, might see Naruto as more of a rival in terms of their ocular powers. Naruto could also use the Byakugan to better understand and help Hinata. He could teach her new techniques based on his own unique understanding of the Byakugan, which could strengthen their bond even more.
If Naruto was born a Saiyan in fanfiction, he'd likely have super strength. He could easily lift boulders or break through solid walls with his bare hands. His speed would also be incredible, able to move faster than the eye can see. And of course, he'd have the ability to fly, which is a common Saiyan ability. His ki blasts would be a powerful weapon, able to blast away opponents from a distance. He might also have the Zenkai boost, getting stronger every time he recovers from a near - death experience.