Another possibility for Itachi's last wish could be the restoration of the Uchiha clan's honor. He dedicated his life to protecting the village, which led to the downfall of his clan. So, perhaps in fanfiction, he wishes for a way to reconcile the village and the remaining Uchiha members, allowing them to once again be respected within Konoha.
First, understand the characters well. Know Itachi's backstory, his motives, and his relationships. For example, his loyalty to the village and his love for Sasuke. Then, think about what kind of wish he might have as an adult. It could be something related to atoning for his past sins or protecting those he loves. Start with a strong opening that sets the mood and the premise of the story. Maybe start with Itachi in a moment of reflection.
One interesting aspect could be stories where Itachi wishes for peace in the ninja world in a more adult and complex way. For example, he might use his skills and knowledge to broker treaties between warring clans. In some fanfictions, his wish could be to see Sasuke grow into a strong and wise ninja without the burden of revenge. This often involves Itachi making sacrifices behind the scenes to ensure Sasuke's development.
If Itachi's last wish is for Sasuke's safety, it could drive the plot by leading Naruto to become even more protective of Sasuke. Naruto might go to great lengths to ensure that Sasuke doesn't fall into the wrong hands or make choices that would endanger himself.
One interesting aspect of Naruto Rule 63 Itachi fanfiction could be exploring Itachi's character from a different gender perspective. In these fanfictions, Itachi might have different relationships with other characters. For example, his bond with Sasuke could be portrayed in a new light, perhaps with more emotional nuances due to the gender - swap. Also, the way he approaches his mission and his loyalty to the village could be re - examined through this new lens.
One plotline could be that female Naruto, with her unique perspective as a female in the male - dominated ninja world, tries to convince Itachi to break free from the chains of his past and the Akatsuki. She might use her own experiences of being an outcast in some ways to relate to him. It's a story about redemption and breaking free from one's dark past.
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.
Naruto would adapt to Itachi's life in several ways. Socially, he'd have to get used to Itachi's connections and rivalries. For instance, his relationship with Kisame would be different as Naruto. He might try to influence Kisame in a more positive way. Emotionally, he'd have to deal with Itachi's internal struggles. Itachi had a lot of guilt and secrets, and Naruto would have to either come to terms with them or find a way to resolve them. And in terms of combat, he'd practice Itachi's signature moves over and over to make sure he could use them effectively in battle.
They could develop a mentor - mentee relationship. Itachi uses his knowledge of the Sharingan to teach Naruto new combat techniques. As they train together, they bond over their shared experiences of loss and their desire to protect the people they care about. Naruto might also help Itachi come to terms with his past actions and find some peace within himself.
One great 'Naruto Itachi Fanfiction' is 'The Redemption of Itachi'. It delves deep into Itachi's complex character, showing his internal struggles and the real reasons behind his actions. It's a heart - wrenching read that gives new perspectives on his relationship with Sasuke and the entire Uchiha clan.