Well, in such a fanfiction, there could be various hints. Maybe Zoro's behavior might be more in line with typical female characteristics described in that specific fictional world, like being more empathetic or having different social interactions compared to the original male - character version. But it really depends on how the author has crafted the story.
Zoro.to might have manga, but it's often associated with copyright infringement and potential security risks. It's better to use legitimate platforms for reading manga.
Well, if we were to consider such stories hypothetically, we might learn about the different aspects of samurai relationships that were perhaps not fully explored in mainstream samurai literature. It could show a side of their emotional and physical relationships that deviated from the traditional view of samurai as solely focused on martial arts and loyalty.
No, it's not a true story. It's likely fictionalized or based on some historical elements but with creative liberties taken for entertainment purposes.