He might be really surprised. Naruto is used to his own world and the fanfiction could show things he never imagined. For example, if the fanfiction has his kids achieving great things in new ways, he'd be proud yet a bit shocked at how creative fans can be.
Naruto would likely be very intrigued. He's always been open - minded. In the fanfiction, if it shows a future where Konoha has advanced technology, he'd be eager to learn more. He might react with a big grin and say 'Wow, this is so cool! I can't wait to see if this could really happen.' He would also be curious about how the other characters in the fanfiction develop and might start thinking about how he can influence their real - life counterparts in positive ways.
He might be shocked at how the village has developed. In some fanfictions, the village could have advanced technology. Naruto, being from a more traditional ninja world, would likely be both amazed and a bit confused at first.
He might be shocked at first. In fanfiction, the future could be full of unexpected changes. He could be excited to see how his friends and the village have developed. Maybe he'd be a bit sad if things didn't turn out as he hoped for his loved ones.
Some characters might be shocked. For example, Naruto himself would probably be really excited to see how his world is imagined in the future. He'd be happy to see that his story has inspired so many different ideas. Sasuke, on the other hand, might be a bit more skeptical. He'd analyze the fanfiction carefully, looking for any inaccuracies or misinterpretations of his character or the ninja world's values.
He would likely be very curious. Naruto has always been eager to learn and explore new things, so seeing future fanfiction would be like opening a door to a new world of possibilities for him.
Naruto might react with a sense of responsibility. If he saw a future where Konoha was in danger, he would feel it was his duty to do something about it. He could start by gathering information from the future vision, like the weaknesses of the enemy. Then, he would share this knowledge with his comrades and come up with a plan to protect the village.
At first, Naruto could be a bit skeptical. He might think it's some kind of trick or illusion. But once he realizes it's really his future self, he would be excited. He would want to know about his future family, if he has one. He'd also be interested in the state of the ninja world in the future. His reaction would be a mix of excitement, curiosity, and a determination to make sure his future turns out as good as his future self's seems to be.
Sasuke, on the other hand, might be more conflicted. He has his own goals and ideals. If he saw a future that didn't align with what he wanted, he might first question the vision. But ultimately, he could also take steps to change it, especially if it involved the safety of his village or his loved ones like Naruto or Sakura. He has a complex personality, so his reaction would not be straightforward.
Naruto would probably have a range of reactions. He could be excited to see new adventures that people have written for him. But if the fanfiction was inaccurate about his character, like making him cowardly when he's known for his bravery, he would likely be a bit miffed. He might also be curious about the new relationships with other characters that the fanfiction presents.
Naruto would be excited and ready to face whatever comes. He's always been positive and believing in his ability to change things. So, he'd see it as a challenge to make the future better.
The older characters such as Kakashi would be cautious. They would recognize Naruto but also be worried about the implications of someone from the future being in the present. They would want to know if his presence could change the future in a negative way. For example, they might fear that his actions could lead to the earlier awakening of a powerful enemy. As for the villains, they might see future Naruto as a threat and try to eliminate him as soon as possible. Orochimaru, for instance, would be very interested in Naruto's future powers and might try to capture him to study. And the new generation of ninja in the past would look up to future Naruto, seeing him as a symbol of what they could become.