Naruto would probably be extremely confused at first. He has always seen Itachi as a complex figure, and suddenly being forced to marry him would be a huge shock. He might feel angry that he has no say in this. Itachi, on the other hand, would likely be stoic on the surface but internally be very conflicted. He has his own burdens and this unexpected situation would add to them.
Naruto might initially be shocked and angry. He has a strong sense of justice and being kidnapped goes against everything he stands for. He would likely try to fight back immediately, using his basic ninja skills and his determination. For example, he could try to use his Shadow Clone Jutsu to create distractions and escape.
Itachi would probably be very calm and composed. He might see Sarada as a symbol of the new generation of ninjas in the village. He could be gentle with her, perhaps sensing her potential and her desire to grow as a ninja.
Sasuke would likely be enraged. Naruto is his rival and also, in a way, his friend. He would immediately set out to find Naruto and confront Itachi. Sasuke has a strong sense of pride and would not let his brother get away with this.
Sasuke would probably be very confused at first. He has spent so much time hating Itachi for what he did to the Uchiha clan. Seeing Naruto befriend Itachi would make him question his own long - held beliefs. He might initially be angry with Naruto for seemingly siding with his enemy.
Naruto would probably be very confused at first. He's always seen the Akatsuki as the enemy, so being taken there by Fem Itachi would be quite a shock. He might be on guard and constantly looking for a way to escape.
There would be other fans who might be intrigued. They like to explore different 'what - if' scenarios in fanfiction. They would see it as a creative way to explore the characters in a new light, even if it goes against the canon. However, they would also be aware that it's just a fictional alternative and not the real Naruto story.
The ninja world would be quite shocked at first. Naruto is from Konoha and has his own set of friends and allies. Fem Itachi was part of the Uchiha clan. Their marriage would be seen as an unexpected union. Some might be skeptical, thinking it was a political move. But those who know Naruto well would understand that it's probably based on true feelings. Konoha's villagers might initially be worried about how Fem Itachi would fit into the village, but Naruto's influence could help her gain acceptance.
He could be touched. Despite his stoic exterior, Itachi may see this as a genuine and innocent gesture from Naruto, and it could warm his heart in some way. Maybe he starts to see Naruto in a new light, as someone who can bring a bit of light - heartedness into his world of shadows.
Definitely include Obito. His complex relationship with the Uchiha clan and his own history with the Anbu - like Akatsuki could create some interesting plot twists. Additionally, Kurenai could be added. She could be involved in a mission where she has to work with Itachi and Naruto. Her genjutsu skills might come in handy during a crucial part of the story. And don't forget about Rock Lee. His determination and unique fighting style could add some action - packed scenes to the fanfiction, especially if he gets involved in a mission with Itachi and Naruto.