It could be a symbolic gesture. Naruto has always been in the spotlight, and covering his face might represent his desire for some privacy or a break from the constant attention. He may be going through a personal transformation and the covered face is a way to show his new, more private self.
Perhaps he's trying to protect himself from some kind of danger. There could be an enemy who is looking for him and by covering his face, he can avoid being detected easily. It could also be a part of a new jutsu or power he has discovered where covering his face is necessary for its activation or control.
One possible reason could be that he is on a secret mission and doesn't want to be recognized. He might be infiltrating an enemy organization or spying on someone. Another reason could be that he has some new power or mark on his face that he wants to keep hidden until he fully understands or masters it.
It could be a new character created specifically for the fanfic. Maybe a rogue ninja from a far - off land who has a vendetta against Naruto. This antagonist might be after Naruto's power or trying to stop him from achieving a certain goal.
One possible reason could be that Naruto is hiding his face to conceal his emotions. In SasuNaru fanfiction, their relationship is often complex and full of unspoken feelings. Naruto might be afraid that Sasuke will read his true feelings if he shows his face. For example, if Naruto has developed deeper romantic feelings for Sasuke, he may not be ready to expose them, so he hides his face as a form of self - protection.
He could use a simple cloth. Just a plain piece of fabric wrapped around his face, like a ninja in a hurry would do. This is a very basic and practical way that is often seen in traditional ninja - themed stories.
Maybe he's trying to hide his identity for a secret mission. In some fanfictions, Naruto might be undercover, and covering his face is a simple way to avoid being recognized.
Another reason could be for disguise. Naruto might be in a situation where he needs to hide his identity. By covering his eyes, which are a very recognizable feature of his, he can make it more difficult for others to figure out who he is. This could be especially important if he is in enemy territory or trying to infiltrate a group secretly.
One possible reason could be for disguise. Maybe he is on a secret mission and doesn't want to be recognized easily. In the Naruto world, there are many dangerous foes, and wearing a face mask can help him blend in or hide his identity from those who might be targeting him.
One possible reason could be that he feels neglected. Maybe his family was always too busy with other things and didn't give him enough attention. This lack of attention during his formative years could have led to feelings of resentment.
Perhaps Naruto is waiting for the right moment to reveal his skills for maximum impact. He could be planning a big surprise for his enemies or wants to make a grand entrance at a crucial time. For example, in a major battle against a powerful foe, he could suddenly unleash all his hidden skills and turn the tide of the battle, which would be more effective than showing them off gradually.
One possible reason could be an enemy attack. A powerful and malicious foe might target Naruto's family to get back at him, and his wife could unfortunately become a casualty in the battle.