Sasuke might be a bit jealous at first. He's always been competitive with Naruto, and seeing Naruto in a special and elite unit like ANBU could trigger that jealousy. He might try to prove that he's just as good or better. Sakura, on the other hand, would probably be worried. She cares a lot about Naruto and ANBU missions are often dangerous.
The reactions could be complex. Team 7 has a deep bond. They might feel left out that Naruto has this new part of his life that they don't fully understand. But also, they would be curious. They'd want to know what Naruto does in ANBU, how he trains, and what kind of missions he goes on. This could lead to them getting closer to Naruto as they try to learn more about his new role.
Some Avengers might be protective. For instance, Captain America could immediately start giving Peter advice on how to better handle his dual identity and keep himself safe. He might offer training sessions to help Peter improve his skills as Spider - Man.
They might be quite surprised. Minato, for example, could be shocked to see how some fanfictions might depict his relationship with his students or his family. Kakashi might find some of the stories about his past quite interesting, while Obito and Rin could have various reactions depending on how they are portrayed in the fanfiction.
Some Avengers might be surprised. Tony Stark, for instance, might be like 'Kid, you're younger than I thought!' and then start to adjust how he mentors Spider - Man. He could become more cautious about the risks he lets Spider - Man take.
It could be a secret mission that the ANBU has been hiding. Maybe it involves a powerful enemy or a dangerous jutsu that they don't want to be known.
Well, the Weasleys are a big family with strong values. Molly Weasley might be shocked at first but then turn into a very protective mother - in - law. Arthur might be a bit more reserved in his reaction but still show his support. Her brothers could have a mix of reactions, some might be overprotective and angry at the person who got Ginny pregnant, while others might be more understanding and focus on helping Ginny.
The Avengers would likely be overjoyed. Tony might crack a joke about Coulson's 'resurrection' while also being secretly relieved. Steve would probably be very happy to see his friend again. Natasha might be a bit more reserved in her reaction but still glad. Thor would see it as a great sign and welcome Coulson back heartily.
It could create a rift within the overall story's world. Fans who love Naruto might not like this portrayal, which could lead to a divide among the fan base. Also, other characters in the story might have to take sides, either with Naruto or with the team that hates him, causing more conflict and drama within the fanfiction.
Well, in some versions, it might start with Team 7 being shocked at first. They may initially doubt Naruto's ability to be in ANBU because they still see him as the goofy Naruto they've always known. But as they see him in action, they start to respect his new role more. Maybe Naruto has to keep some secrets from them initially which causes some tension within the team, but eventually, they come to accept and support his position in ANBU.
In some fanfictions, Naruto is completely devastated. He might go into a state of shock at first, unable to believe the news. Then he could be filled with intense grief and anger, blaming himself for not being there to protect Jiraiya.
Some of the knights could be a bit jealous. Immortality means having an infinite amount of time, and they might envy Merlin for that. But at the same time, they would also be very protective of him, knowing that his immortality could make him a target.