There must be 5 or more fanfics with Orochimaru as the protagonist, but none have more than 10 chapters.
I think it's a great wasted opportunity, I would love to see a novel with a protagonist reincarnated as Orochimaru as a child.
I only ask that the protagonist has the same motivation as Orochimaru to learn all the existing jutsus, found the Sound Village and have a bit of Orochimaru's psychotic personality.
The only thing similar to this was a novel where the protagonist is Orochimaru's apprentice, but I think that was also dropped after 60 chapters.
Anyway, I don't need to explain much more why this would be a great story. Thank you for your attention.