Sakura would likely be initially terrified but quickly regain her composure. She is a trained ninja after all. She might start by assessing her situation, looking for any weaknesses in Team Hebi's defenses or any possible escape routes. Sakura would also try to talk her way out of the situation, using her intelligence to reason with Team Hebi. If that doesn't work, she would be ready to fight back using her taijutsu skills and any medical ninjutsu that could be used offensively, like her chakra - enhanced strength punches.
Sasuke would also be deeply affected. He might show his concern in a more reserved way compared to Naruto. He could be seen as being more determined to find a solution, using his skills and knowledge to try and save Sakura. He might even feel a sense of guilt if he thinks he could have prevented it in some way.
Some popular Naruto and Sakura angst fanfictions include 'Heartache'. It explores the emotional turmoil between them when Sakura realizes she might be losing Naruto to his new responsibilities. 'Unspoken Pain' is another. It shows how they both have secrets and pain that they don't share with each other. 'Grieving Souls' is also a great read as it focuses on the times when they are both dealing with the loss of comrades and how it affects their relationship.
The popularity of Naruto and Sakura angst fanfictions comes from the fact that fans are always interested in exploring the what - ifs. What if their relationship had more problems? What if they couldn't be there for each other? These fanfictions allow for a more in - depth look at their characters and how they would react in difficult situations. Also, the angst adds a layer of drama that many readers find appealing.
A common theme is unrequited love. As mentioned before, the original dynamic between Naruto and Sakura had elements of this. In fanfiction, this can be exaggerated, with Naruto pining for Sakura who is still hung up on Sasuke for a long time. Another theme is sacrifice. Writers might create situations where Naruto or Sakura has to sacrifice their own happiness or even their lives for the other. For example, Naruto might sacrifice his chance at becoming Hokage to save Sakura. Also, misunderstandings often play a big role. They could misinterpret each other's actions or words, leading to more angst in the relationship.
Sakura would be heartbroken. She'd likely spend hours upon hours by Naruto's side, trying to jog his memory with stories of their adventures together. She might even get a bit overbearing in her attempts. Sasuke, who has his own complex relationship with Naruto, would be conflicted. He'd see Naruto's forgetfulness as a sign of weakness at first but then realize the importance of their bond. Kakashi, being the experienced leader, would start by observing Naruto carefully to see exactly how much he has forgotten and then start a systematic process of helping him remember.
Sakura could also use her strength in combat. In the fanfiction, she may have developed new jutsu or fighting techniques that she uses to protect her teammates and help them achieve their goals. For example, she could use her precise chakra control to enhance her attacks and defenses, making her a valuable asset in battles.
Sakura would probably be angry at herself for being captured. She's a proud ninja. So she would start looking for weaknesses in Itachi's hold on her. Maybe she would try to engage him in conversation to find out his motives, all the while formulating a plan to break free. She could also try to send out some sort of signal to her comrades if possible.
She would be both curious and empathetic. Curious about how the baby ended up where she found it and empathetic towards the baby's situation. So she would start to form an emotional bond with the baby right away. She might talk to the baby softly, trying to soothe it, and then start making plans on how to best care for it in the long run.