The fanfiction with Naruto born the same age as Itachi would rewrite a lot of the plot. Naruto would grow up in a different environment. He'd be in the same age group as the older, more advanced shinobi. This could lead to him having different mentors. Instead of Jiraiya, he might have been trained by someone else. His understanding of the ninja world's politics would also be different. He would be more aware of the Uchiha - Konoha situation from a younger age. And his bond with Sasuke would form under different circumstances, perhaps with both of them being more evenly matched in their growth and development from the start.
If Naruto was born the same age as Itachi, the story would be drastically different. Naruto would be more mature and skilled earlier. He might have been involved in the Uchiha massacre situation. Maybe he could have even tried to prevent it, given his nature of not wanting to see people suffer. This would also change his relationship with Sasuke. Instead of being an older peer, he would be more of an equal in age, and their rivalry could take on a different dynamic, perhaps more of a mutual understanding from the start.
Well, in a fanfiction where Naruto is born the same age as Itachi, Naruto would likely have a different set of skills and experiences. Since Itachi was a prodigy, Naruto being the same age might mean he'd be pushed harder in his training. He could have been part of the same generation of shinobi that Itachi was. This would mean different interactions with the Akatsuki as well. He might have had to face off against them much earlier in his life, and his growth as a ninja would be shaped by these early and more challenging encounters.
Their relationship would likely become more of a friendly rivalry. Since they are the same age, they would constantly be comparing their progress in ninjutsu and other skills. Naruto would probably be more eager to prove himself against Itachi, and Itachi might see Naruto as an interesting opponent.
The story would be transformed in many ways. Naruto, being as old as Itachi, would have had different training experiences. He might have been trained by different people or in different ways. This would lead to different jutsu and abilities. In the political arena, Naruto could have played a more active role in preventing the Uchiha - Leaf Village rift. His relationship with characters like Kakashi and Jiraiya would also be different. For instance, he might have been more of an equal to Kakashi, and Jiraiya might have had different expectations of him. All these changes would create a whole new narrative for the Naruto story.
If Naruto was born with Mokuton, the story would change significantly. For one, his relationship with the Hidden Leaf Village might be different. The Mokuton was a feared and powerful ability due to its connection with the First Hokage. Naruto could be seen as a greater threat initially. He might also have been trained differently. Instead of focusing on the Rasengan and Sage Mode, he could have been taught more nature - based jutsu related to Mokuton earlier on. This could have led to him being more powerful at a younger age and potentially changing the outcomes of many battles, like the fight against Orochimaru where he might have been able to defeat him more easily with Mokuton - based attacks.
Well, if Naruto was born in Iwa, the whole story would be flipped on its head. For one, he'd grow up with different values and training methods from Iwa. His relationships would be completely different. Instead of having friends like Sasuke and Sakura from Konoha, he'd have Iwa comrades. His ninja way might be more in line with Iwa's harsh and competitive environment. Maybe he'd be more aggressive in his fighting style. Also, the relationship between Iwa and Konoha would be more complex as Naruto could potentially be a bridge or a source of conflict between the two villages.
If Naruto was born the same age as Itachi in fanfiction, it would change the power balance in the village. Naruto could be part of the decision - making processes earlier. His influence on the Uchiha clan's fate might be significant. He could use his unique ability to persuade and his strong will to try and bridge the gap between the Uchiha and the village. Also, his interactions with Kakashi would be different. Instead of Kakashi being an older, more experienced mentor, they could be more like comrades or even rivals in some aspects.
If Naruto were Itachi's twin in fanfiction, it would have a huge impact on the plot. Naruto would grow up with different values perhaps, influenced by the Uchiha clan's way of thinking. His goal might not be just to become Hokage in the traditional sense. He could be more focused on avenging the Uchiha clan or restoring its honor. The power balance in the village would shift too. The Uchiha clan might have a stronger standing with Naruto being part of it. And the mystery surrounding Itachi's actions would take on a new meaning for Naruto, as he'd be directly related. He might be more involved in uncovering the truth about Itachi's motives much earlier in the story.
Their relationship with Sasuke would be very different. Naruto might not look up to Itachi as much as in the original story, and Itachi might not see Naruto as a potential threat to Sasuke's growth. Instead, they could both be like older brothers to Sasuke, guiding him in different ways.
Well, if Naruto was born with the Sharingan, it would completely disrupt the original power dynamics. He'd have an edge in combat from the start. For example, he could quickly copy jutsu like Sasuke does with his Sharingan. This might make his early training with Iruka and Kakashi very different as he'd already have a powerful dojutsu at his disposal.
If Naruto was born a Saiyan, the entire Naruto storyline would be completely different. For starters, he'd likely have a tail and the ability to transform into a Great Ape. His power level at a young age would be much higher than in the original story. Instead of learning ninja techniques like the Rasengan, he might focus on mastering Saiyan ki blasts. His goal might not be to become Hokage but rather to become the strongest Saiyan in the universe, or at least on Earth. Also, his relationships with characters like Sasuke would change. Sasuke might see Naruto as an even greater rival, not just in ninja skills but also in raw power.
If Naruto was born as a girl in fanfiction, the initial dynamic with Iruka might be different. Iruka could be more protective. Also, Sasuke might view her in a different light, perhaps with a more complex mix of rivalry and underlying affection. And Naruto's relationship with Sakura could be more of a sisterly bond rather than a love triangle situation. It could also lead to different interactions with Jiraiya, who might train her differently or have different expectations.