Yes, he might be. In some fanfiction universes, the author could reimagine Harry as the first Sith. This could be a really interesting twist on the original character, creating a whole new story arc full of dark side powers and different moral challenges compared to the traditional Harry Potter story.
I don't know who specifically created 'harry the sith fanfic'. There are so many fanfic authors out there, and it could be someone from any corner of the internet who was inspired by both Harry Potter and Star Wars and decided to create this unique mash - up story.
I'm not sure specifically as there could be many different 'harry the sith fanfic' stories. It might be a fan - created story that combines elements of Harry Potter (assuming Harry here refers to the character from that series) and the Sith from Star Wars. It could involve Harry somehow getting involved with Sith - like powers or the Sith culture in a fictional and creative way.
The length of the Sith Warrior story can vary depending on how quickly you progress and how much side content you explore. Generally, it can take a significant amount of time to complete the main storyline.