Naruto would surely be one of the first to try and rescue Sakura. He has always been protective of her and would not stand by while she's in danger.
Sasuke might also be involved in the rescue. Despite their complicated relationship, he still has some feelings for Sakura. And he wouldn't want to see her in the hands of someone like Deidara. Also, Kakashi, as their former sensei, would likely lead a rescue mission. He has the skills and experience to deal with Deidara's explosive attacks and find a way to save Sakura.
One possible plot for a 'kisame kidnaps sakura fanfic' could be that Kisame mistakes Sakura for someone else who has wronged his organization. He quickly grabs her and takes her away. Sakura, initially terrified, soon realizes the misunderstanding. She then tries to convince Kisame of his error while also looking for opportunities to free herself. Meanwhile, her friends from the village start a search and rescue mission, leading to a series of intense confrontations between the rescuers and Kisame's allies.
Sakura is smart, so she might try to outwit Madara by pretending to be compliant at first. She could start a conversation with him, trying to find out his motives and weaknesses. Then, when the time is right, she could use her chakra control skills to break free from any bindings and make a run for it. Maybe she would also try to send a hidden signal to her teammates if she gets the chance.
Sakura would probably be initially very angry. She has strong feelings for Sasuke, but kidnapping is a very extreme act. So she would likely fight back, using her medical ninjutsu skills and combat abilities to try and escape.
One possible plot could be that Sasuke has some sort of misunderstanding. Maybe he believes Sakura has some information about a threat to Konoha that she's not sharing, so he kidnaps her to force her to talk. Then Sakura tries to convince him that he's wrong while also trying to understand why Sasuke has become so extreme.
It could be that Itachi is being controlled by some dark force or an enemy. He doesn't really want to harm Sakura but has no choice. The fanfic might then focus on Sakura trying to figure out how to break the control on Itachi while also trying to escape from the situation. She could use her medical ninjutsu skills to her advantage in some way.
There could be. Fanfiction writers often come up with unique and unexpected ideas. Given the creativity in the fanfiction community, a story where Sakura is Kisame's daughter is not out of the realm of possibility. You can try searching on popular fanfiction websites to see if it exists.
Yes, there might be such fanfictions in the vast world of fan-created content. Some fans like to create unique family relationships between different characters from various anime, and this could be one of those interesting concepts.
One common theme is the clash of personalities. Sakura is often portrayed as strong - willed and determined, while Kisame is more of a stoic and powerful antagonist. So their interactions are filled with tension.
Yes, there are some out there. You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'kisame and sakura' and you'll find various stories that explore their relationship in different ways.