Kakashi could be another character to rescue Sakura. He is a very experienced ninja and has mentored Sakura in the past. He might use his Sharingan or some of his unique jutsu to outwit the clone Itachi and free Sakura. And he's always looking out for his students, so it would be in character for him to step in and help.
There could be many authors who might write such a fanfiction. It could be an amateur writer who is a big fan of the Naruto series and just wanted to explore this particular scenario between Sakura and Itachi.
She could use her brute strength enhanced by chakra to try and break free. If she can concentrate enough chakra to her limbs, she might be able to overpower Itachi's hold for a moment and create an opening to escape.
The main characters in this fanfiction are Sakura and Itachi's clones. Sakura, with her own set of skills and personality traits, is the focus of the story as she endures the struggle. Itachi's clones bring the conflict into the story. They may possess some of Itachi's signature abilities, like the Sharingan, which could make them extremely difficult for Sakura to handle. Their presence forces Sakura to use her own strength, whether it be her physical combat skills or her intelligence, to try and overcome the situation they've put her in.
In this fanfiction, perhaps Sakura is struggling because the clone of Itachi has some sort of special power or ability that she is unable to break free from. It could be related to genjutsu, and she's constantly fighting against the illusions while in the grip of the clone. Another possibility is that she's in a moral dilemma while in this situation, for example, if she has to make a choice between saving herself or sacrificing for the greater good.
I'm not sure specifically as I haven't read this exact fanfiction. But it might be about Sakura facing some sort of challenges while in the grip of Itachi's clones. It could involve battles, or perhaps some sort of emotional or mental struggle against the power or abilities of Itachi's clones.
Sasuke could be a likely candidate. He has a connection with Sakura and also has a lot of power. He might sense that Sakura is in trouble and come to her rescue. He could use his Sharingan to counter Orochimaru's jutsu if it comes to that.
The concept of Sakura struggling in Itachi's tight grip in fanfiction is quite interesting. It could be a physical struggle, like she's trying to escape his hold. Or it could be more of an emotional or mental struggle. For example, if Itachi is using some form of mind - control or manipulation. This situation can also lead to different plot twists. Perhaps Sakura discovers a new power or ability while in this struggle, or she forms an unexpected alliance to free herself.
Well, in such a fanfiction, Sakura might struggle because Itachi is an extremely powerful and complex character. His motives are often mysterious. Maybe Sakura is trying to break free from his grip physically or mentally. For example, she could be held captive in a situation where she has to use her own skills and knowledge to outwit Itachi. It could also be a situation where she is caught in the middle of Itachi's plans that she doesn't understand at first.
Naruto could be the one to save her. He has a strong bond with Sakura and would never let her be in danger for long. His powerful ninja skills and his unwavering determination would make him a likely candidate to rescue her from Black Zetsu's grip.
In this kind of fanfiction, Sakura might be in a very dangerous situation. She could be facing Itachi's powerful jutsu while struggling in his grip. Itachi is a very strong character, so Sakura may have to use all her skills and knowledge just to survive. Maybe she'll try to break free and find a way to counter Itachi's moves.