Kakashi could also be included. He has a history with Obito, and his relationship with Itachi was also complex. His skills and his role as a mentor - like figure can bring a different dynamic to the story. For example, he could be the one who suspects something strange is going on between Itachi and Obito and tries to figure out their motives.
In this fanfiction, Itachi might help Sakura become stronger by training her in various ninja skills. He could teach her advanced genjutsu techniques. For example, he might start with the basics of detecting and breaking genjutsu, and then gradually move on to creating complex illusions herself. This would enhance Sakura's ability to defend against and use genjutsu in battles.
One idea could be a story where Itachi and Obito are forced to team up against a new, powerful enemy that threatens the ninja world. They start off distrusting each other due to their past actions, but as they face challenges together, they gradually come to understand and respect one another.
Well, it depends on the specific fanfic. Some fanfics might focus on Naruto's growth post - Shippuden and give him abilities that make him stronger than Itachi. For example, they could have Naruto master a new form of Sage Mode that gives him an edge over Itachi's Sharingan - based techniques. However, other fanfics might keep Itachi's power level relatively high and not have Naruto overtake him. So, there's a lot of variation among different fanfics.
Often, in fanfic, Naruto is made stronger than Itachi because the writers want to explore new story arcs. If Naruto is stronger, new and exciting battles and relationships can be created. For instance, Naruto could be the one to protect Sasuke from Itachi in a different way. Also, Naruto's positive and determined nature makes him a popular character to be super - powered in fanfics.
Naruto could be one of his allies. Naruto has this knack for seeing the good in people and would probably be willing to give Obito a chance to redeem himself. Also, Sakura, with her skills as a medic - ninja, could be an ally. She might help heal Obito if he was injured during the war and see the potential in him to be a force for good.
There could also be interactions with the new generation of ninjas. They might view Obito as a sort of legend or a cautionary tale. Their fresh perspectives could either inspire Obito to change further or make him feel even more out of place in this new post - war ninja world.
Besides Obito, Sasuke could be a main character in this fanfiction. Sasuke, with his own journey of redemption and his understanding of power and the ninja world, could have an interesting dynamic with the reincarnated Obito. Also, Sakura might play a role. She could be the one who tries to heal the reincarnated Obito, both physically if he is injured during his new adventures and emotionally from the traumas of his past life.
One possible plot development could be that as Sakura gets stronger with Itachi's help, she starts to gain the attention of other powerful shinobi. This could lead to some jealousy or admiration within the ninja community. For instance, some might see her new - found strength as a threat, while others might want to learn from her.
Minato might also be a prominent character. As their teacher, he can influence the way Obito and Kakashi interact. In some fan fictions, he could be the one to help them resolve their differences or provide some crucial information about their past that changes their current situation.