One idea could be exploring Kakashi's relationships within the Anbu. For example, his friendships or rivalries with other members. Maybe there was a particular mission where he had to rely on a teammate he didn't trust at first.
A fun plot could be a time - travel fanfiction where Kakashi is sent back to his Anbu days with the knowledge he has now. He could use this knowledge to change certain events, like saving a fellow Anbu member who died on a previous mission, or preventing a political intrigue within the Anbu that had far - reaching consequences.
Another plot could be about Kakashi's struggle with the darker aspects of Anbu work. He's a complex character, and showing how he copes with the morally gray areas of assassination and espionage in the Anbu would be fascinating. It could involve him having to make a tough choice between following orders and his own sense of right and wrong.
One idea could be that Sakura and Kakashi are on an Anbu mission together and they encounter a powerful enemy that requires them to combine their skills in new and unexpected ways. For example, Sakura's medical ninjutsu could be used not just for healing but also to enhance Kakashi's Sharingan abilities temporarily.
Perhaps a story where Kakashi's past Anbu experiences resurface during a mission with Naruto in the Anbu. They have to deal with an old enemy that Kakashi thought was long gone, and Naruto helps him come to terms with his past traumas.
One idea could be that Sakura, as an Anbu, travels back in time and tries to prevent certain tragedies in Kakashi's past. Maybe she stops Obito from 'dying' initially, which would change the entire Naruto storyline in a major way.
One idea could be that Naruto joins the ANBU under Kakashi's strict training. He struggles to adapt to the ANBU's stealthy and often morally gray missions at first. For example, he might be conflicted when ordered to spy on a former ally. But with Kakashi's guidance, he learns to balance his ninja ideals with the demands of the ANBU.
One idea could be exploring the character's past in the ANBU in more detail. For example, showing the difficult missions they had to undertake and how it shaped them.
One idea could be exploring Itachi's time in ANBU and how Naruto might have influenced his decisions secretly. Maybe Naruto, with his unique way of seeing people, could have made Itachi question his path in the ANBU more deeply.
Another plot could involve the Anbu team being tasked with protecting a young and powerful ninja from another village who has valuable knowledge. Along the way, they form an unexpected bond with this ninja and learn new techniques from them.
One idea could be that the blind Anbu has a special ability to sense chakra in a unique way. For example, they can detect the slightest change in an enemy's chakra, even if they can't see them physically. This gives them an edge in battle.
One idea could be Naruto going on an Anbu mission where Hinata secretly follows him to protect him. Another could be an alternate universe where Naruto and Hinata are both in the Anbu and they have to work together to solve a mystery within the Hidden Leaf. Or perhaps a story where Naruto is in the Anbu and Hinata is trying to get his attention in a more covert way than usual.
One idea could be that Naruto and Sasuke are assigned a top - secret ANBU mission together to infiltrate a hidden enemy base. They have to rely on their unique skills and their new - found understanding of each other as ANBU operatives. Another could be that they are both part of an elite ANBU squad and have to deal with a powerful rogue ninja who has ties to their past.