In this fanfic, Naruto might face tougher and more secretive missions. He could be trained in new and deadly ninja techniques specific to ANBU. Also, his relationships with other characters might change. For example, he might become more distant from his old friends as ANBU work often requires secrecy.
One possible plotline could be Sakura using her medical skills in a new way in the ANBU. For example, she might develop new medical jutsu to heal ANBU members during dangerous missions more effectively.
In some fanfictions, Naruto might join Anbu because of Sakura to prove himself worthy of her. Maybe he thinks that by becoming an elite Anbu member, he can show her that he's strong and reliable.
The main characters are obviously Itachi and Sakura. Itachi is a complex character from the Uchiha clan known for his powerful Sharingan abilities. Sakura, on the other hand, is a skilled kunoichi who has grown in her medical and combat abilities. In this fanfiction, they are usually placed in the context of the ANBU, which is a special and secretive part of the ninja world.
One possible fanfiction could be about Sakura joining an Anbu team that has Itachi and Shisui. Maybe Sakura is a new recruit and she has to learn from the two experienced shinobi. Itachi could be the calm and collected leader, while Shisui is the more easy - going one who helps Sakura adjust to the harsh Anbu lifestyle.
There is a fanfic called 'Itachi and Sakura: Anbu Allies'. It delves deep into their Anbu experiences. The author does a wonderful job of depicting the Anbu world and how Sakura and Itachi's skills complement each other. It also has a great plot that keeps you hooked from start to finish.
Their relationship could be developed through a series of flashbacks. For instance, Itachi could recall moments from Naruto's childhood that he observed while in the ANBU. These memories could make him see Naruto in a new light. Meanwhile, Naruto could learn about Itachi's past and the sacrifices he made. This exchange of knowledge could build a bond between them based on empathy and respect. In addition, they could train together in secret, with Itachi teaching Naruto some of his ANBU skills, which would also strengthen their relationship.
Well, in such a fanfiction, perhaps Naruto has just lost Sasuke again and is deeply depressed. The ANBU, seeing his skills and his need for a distraction, recruit him. He starts off being a bit of a misfit in ANBU, not following all the rules because of his independent nature. But as he continues, he starts to understand the importance of their work. He might even form new bonds with his ANBU comrades, which slowly help him come out of his depression.
In this fanfiction scenario, Sakura might gain a whole new level of combat skills. She could learn stealth techniques from Anbu Kakashi. This would make her a more formidable ninja in the story. Maybe she would also be involved in some top - secret missions and form a closer bond with Kakashi during those dangerous operations.
Well, Naruto might face a whole new set of challenges. In the ANBU, he could be pushed to his limits physically and mentally. Maybe he'd use his unique skills in stealthier ways compared to his normal fighting style. Also, his relationships with other ANBU members would be interesting to explore, as he's a bit of an outlier with his loud and brash personality.