Perhaps he has hidden the full extent of his Sage Mode abilities. He might be able to stay in Sage Mode for a much longer time than he has shown so far, or have some other undisclosed powers within that mode, like the ability to sense enemies from much greater distances.
He could be hiding from Orochimaru. Orochimaru has always been interested in Naruto's power. Maybe Naruto has discovered a new power that Orochimaru wants even more desperately, so he hides behind a mask to avoid Orochimaru's detection.
Naruto might end up feeling extremely lonely. His family has always been an important part of his life. Without their support and presence, he could become depressed or start making even more reckless decisions. Also, if his family tries to search for him, they could get into danger themselves in the process, which would be an unintended consequence of his hiding.
The story's plot could also take different turns. Instead of the usual challenges he faces as a male ninja, he now has to deal with issues related to hiding his gender. This could include things like disguising his appearance more carefully and avoiding situations where his gender might be discovered.
Yes, there are such fanfictions in the Naruto fanfiction community. Some fans like to explore unique and creative scenarios in their writing, including this rather unexpected one.
Well, in such fanfiction, one idea could be that Naruto hides his gender to gain an advantage in a male - dominated ninja world. Maybe he feels that as a female, he'd be underestimated or treated differently. So by hiding it, he can prove himself on equal terms.
One possible reason could be that his eyes hold a special power that he doesn't want others to discover easily. For example, it might be a new type of Sharingan or a unique ability related to his Uzumaki heritage that he needs to keep secret to protect himself or those around him.
Maybe he wants to surprise his opponents in battles. He could be waiting for the perfect moment to reveal his full power and turn the tables on his enemies.
One possible reason could be that he doesn't want others to pity him. Naruto has always been a proud and strong - willed character. His scars might be a reminder of painful past experiences, and he prefers to deal with them privately rather than showing vulnerability to others.
Well, one possibility could be that Naruto is hiding his true identity or emotions. Maybe he's on a secret mission and the mask helps him blend in or deceive the enemy. He could be using it as a form of protection, not just physically but also emotionally.