Maybe he was attacked by a rogue ninja with a special weapon that damaged his eye. This would be a tragic event that could change his perspective on the ninja world and his role in it. The eyepatch would then be a constant reminder of that fateful encounter.
There might be a fanfiction where Naruto's eyepatch is actually a magical or chakra - infused item. It could have been given to him by an ancient sage, and it gives him special powers like enhanced perception or the ability to see through genjutsu more easily. This would add an exciting new aspect to his character.
In certain comic arcs, Thor is depicted with an eyepatch. This is often part of his character's evolution or due to specific events within the comic universe.
Maybe he got injured in a new dark wizard battle. The eyepatch could be a sign of his sacrifice and new - found determination. It would add a cool, rugged look to his character and could lead to new relationships as people view him differently.
An eyepatch on the left in stories could imply that the character is trying to protect their left eye for some reason. It might also be a fashion statement to make them look more intriguing or tough.
He may develop a more reckless side. Feeling like he has something to prove now that he has this 'disability' of sorts. He could be more willing to take risks in battles, thinking that he has less to lose. This new - found recklessness could either lead to great victories or put him and his friends in more danger than before.
Yes, there are likely fanfictions out there where Naruto has a zanpakuto. Fanfiction writers often like to cross over different anime concepts. They might give Naruto a zanpakuto from the Bleach universe to explore new storylines and character developments. It can lead to really interesting scenarios where Naruto has to learn to use the zanpakuto's powers, which are quite different from the chakra - based abilities in Naruto's original world.
There could be such a fanfiction. The world of fan - created content is full of surprises. Writers might be inspired to give Naruto the power of Hamon for several reasons. It could be to create a more complex power system in the Naruto world, or perhaps to introduce a new type of threat that only Hamon can counter. Maybe they want to see how Naruto's friends and foes would react to this new ability. So, while I can't say for sure, it's very likely that it exists out there in the sea of fanfiction.
Yes, there are likely Naruto fanfictions that involve Lucario. Fanfiction writers often create crossovers between different fandoms, and the idea of Naruto having an encounter or some sort of connection with a Lucario from the Pokémon universe can be an interesting concept for many writers to explore.