One possible reason is their physical appearance. They might have some similar facial features or hair color that could give the impression. Another reason could be their skills. If in fanfiction, Tobirama's skills are exaggerated and Naruto has similar - looking skills, it could lead to this idea. Also, their status in the ninja world as important figures might contribute.
I'm not entirely sure. While Naruto and Tobirama have their own distinct characteristics, some might see a resemblance in terms of their roles in the ninja world. Tobirama was a key figure in building the village infrastructure and Naruto was crucial in uniting the village. However, just because of these parallels, it doesn't necessarily mean Naruto looks like Tobirama fanfiction. It could be just a creative idea that some fans have.
It could be just for the fun of it. Writers often like to play with the established characters and create unique scenarios. In this case, seeing strong Naruto in a girl - like form can lead to humorous situations, like when his friends first see him and their shocked reactions. Also, it can open up new plotlines, such as Naruto having to disguise himself as a girl for a mission and having to navigate the situation while still being his strong self.
One reason could be to create a new power dynamic. If Naruto was Madara's reincarnation, it would bring a whole new set of powers and abilities into play. Another reason might be to explore a different kind of character development. By having Naruto be Madara's reincarnation, the fanfic author could take Naruto on a different journey, perhaps one that involves more of Madara's ruthlessness or strategic thinking. Also, it could be just for the shock value, to present readers with a completely unexpected twist on the characters they know so well.
One possible scenario is when Naruto travels back in time in the fanfiction. He might end up looking like Minato as a result of some time - traveling magic or jutsu side - effect. This could lead to all kinds of interesting situations, like his friends not recognizing him at first.
Well, it's interesting because both characters have their own unique charm. Naruto is all about hope and bringing people together, and Tobirama was a brilliant strategist. In a fanfiction where Naruto is like Tobirama, we might see Naruto using his charisma to implement Tobirama's strategic plans. It could also explore how Naruto would deal with the same political and social issues that Tobirama faced in his time. This kind of cross - over in character traits can create a rich and complex story that fans can really sink their teeth into.
Also, Tobirama was a master of space - time ninjutsu. Naruto has some experience with space - time with his teleportation jutsu, but Tobirama's were more advanced. Naruto would need to understand and master these complex techniques if he wants to truly fight like Tobirama. It would take a long time and a great deal of effort to reach that level of proficiency.
Well, it could be that the fanfiction is set in a very different universe where Naruto has different upbringing or experiences. But this is quite a stretch because Naruto's caring side is so deeply rooted in his story. It might also be that the writer is simply trying to create shock value by presenting such a counter - intuitive view of Naruto. But in general, it's not in line with the essence of Naruto as we know him from the original series, and it might be a bit of a gimmick to make the fanfiction stand out in a sea of more traditional Naruto stories.
There could be a story arc where Naruto uses his new appearance as a girl to his advantage in espionage or undercover missions. This would bring in elements of mystery and intrigue. His interactions with other villages' ninja would also be different, and he could use this to gain information or form new alliances in a way that he couldn't as a male Naruto.
It could be that Naruto is trying to prove himself. He wants to show that he can be as great a fighter as his father. Also, he might have received some training or knowledge transfer from someone who knew Minato well. This could have inspired him to adopt Minato's fighting style. He may also be in a situation where his normal fighting style isn't working, so he turns to Minato's as a last resort.
Maybe Naruto is put in a situation where he feels that Hiruzen's way of handling things is the best option. For instance, if there is a major crisis in the village that requires a more traditional and experienced approach, Naruto might choose to act like Hiruzen. Also, he could be influenced by the stories he has heard about Hiruzen and wants to fill his shoes in a way.