He'd probably be shocked. His world is already full of surprises like different jutsus and powerful enemies, but the multiverse would be on a whole new level. He might not believe it at first and think it's some kind of elaborate prank or illusion.
Naruto would likely be very curious. He has always been eager to learn new things. So, he would dig deeper into the fanfiction, trying to understand the rules of these different universes. He might even start looking for similarities between his world and those in the multiverse, thinking that there could be some hidden connections.
He might be really excited. Naruto loves new and exciting things, and the multiverse fanfiction would be full of that.
Harry Potter might react with a mix of fascination and disbelief. On one hand, he would be drawn into the imaginative scenarios presented in the multiverse fanfiction. He might be excited to explore the different possibilities of his life and the lives of those around him. For instance, seeing a universe where Hagrid is a powerful wizard instead of a gamekeeper. On the other hand, some of the more outlandish ideas in the fanfiction might make him skeptical at first. But overall, he would likely be very interested in this new way of looking at his world and the magic within it.
He might be entertained. The abridged versions often have humor and can make light of serious situations in the original Naruto story.
They may find it funny. There are often humorous fanfictions that could make them laugh.
They could have a range of reactions. Naruto would likely be excited and eager to see new stories about his world. He loves adventures and would be interested in seeing different takes on his life.
Naruto would be thrilled. He loves being the center of attention and seeing all these stories about him would make him feel even more important. He'd probably want to meet the writers and tell them how cool he thinks their ideas are.
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 would likely be excited. He loves his son so much that seeing different stories about Boruto would be like seeing different potential futures for him. He might even get some inspiration from the fanfiction to give Boruto some advice in real life.
Kakashi would be very observant. He would look for how the fanfiction writers understand the world of Naruto, the values and the moral lessons. He might even use some of the creative ideas from the fanfiction in his own teachings if he thought they were valuable and in line with the spirit of the original story.
He might be really amazed. He'd see different versions of his world and himself, which could make him think about his own life and choices in a whole new light.