Well, in this kind of fanfic situation, Sakura could also become more protective of Naruto. Since a jinchuuriki is in a rather dangerous position, she might start to see him as someone who needs her support more than ever. She could try to keep his secret safe from those who might want to harm him because of it.
Some of his other friends might react differently too. Some may be more cautious around him, worried about the power of the jinchuuriki within him. But those who truly trust Naruto, like Shikamaru, might not change their attitude much. They would see that Naruto is still the same person he was before, just with this added aspect to his identity.
She might be initially shocked. Sakura has always seen Naruto as a friend, so learning of his romantic feelings could completely change her perspective of him. It could make her re - evaluate all their past interactions.
Another development could be that Sakura starts to develop feelings for Naruto as she spends more time thinking about his love for her. She might notice things about him that she never paid attention to before, like his kindness and determination in a more romantic way.
In many fanfictions, it might start with Sakura noticing small things about Naruto that she hadn't paid much attention to before. For example, his unwavering determination in the face of difficulties. This newfound awareness gradually grows into admiration and then love as she spends more time with him, either on missions or during downtime in the village.
In this fanfiction, Naruto Jinchuuriki might have god - like powers such as extreme strength. They could potentially have the ability to control nature on a large scale, like summoning massive storms or earthquakes. Their physical endurance might be enhanced to the point where they can withstand attacks that would normally be fatal.
In a Sakura Cardcaptors fanfic where Chelsea finds out, she might react in different ways. She could be shocked and initially not believe what she has discovered. For example, if she finds out about Sakura's secret cardcaptor identity, she may question how such a thing could be possible in the seemingly ordinary world they live in.
She might be overjoyed. After all, Naruto is her son. She could immediately rush to find him and embrace him tightly, tears of happiness streaming down her face.
Well, one possibility is that Dark Naruto would be overjoyed. After all, Kushina is his mother. But at the same time, he could be very conflicted. His dark side might make him suspicious of her motives. He could test her in various ways to see if she's really who she says she is. And Kushina, on her part, would probably be heartbroken to see what her son has become.
One possible reason could be that Naruto finally realizes Sakura's true feelings for Sasuke are unwavering. He might come to understand that his constant pursuit is fruitless and decides to respect her feelings and stop asking her out.