You can try Archive of Our Own (AO3). It has a large collection of fanfics, including many Sasusaku blank - period ones. Just search for the relevant tags and you'll likely find what you're looking for.
One good Sasusaku blank - period fanfic is 'A New Beginning'. It delves into Sasuke and Sakura's relationship during that time in an interesting way. They face various challenges together and it shows their growth as individuals and as a couple.
One common theme is growth. Both Sakura and Sasuke are growing as individuals during the blank period, and fanfictions often explore how this growth affects their relationship. Another theme is forgiveness. Sasuke has a lot of things he needs to be forgiven for, and Sakura's role in that forgiveness process is often a central part of the story.
Sasuke is also a great choice. His relationship with Naruto is always a central point, and during the blank period, we can see how he's adjusting to life back in the village or if he's still on his own path of redemption. And his unique powers can bring a lot of action to the story.
One great Sasuke Sakura blank period fanfic is 'A New Beginning'. It focuses on how they both grow individually during the blank period and then how their paths cross again in an unexpected way. The character development in this fanfic is really well - done.
Anti Sasusaku fanfic focuses on going against the Sasusaku relationship. So, while regular Sasusaku fanfic might show the growth and love between Sasuke and Sakura, anti ones would show the opposite. For example, they could show Sasuke constantly rejecting Sakura or having a negative view of her.
One idea could be exploring Naruto's travels to different hidden villages during the blank period to learn new jutsu. He might encounter unique shinobi with strange powers.
The love - hate aspect often adds depth to the Sasusaku relationship in fanfic. Love is obvious as Sakura has been in love with Sasuke since they were young. But the 'hate' can come from external factors too. In some fanfics, the ninja world's views on their relationship or the actions of other characters can cause strain. For instance, if other characters try to split them apart, it can create a sense of 'hate' towards those interfering forces.
In sasusaku lemon fanfic, one characteristic is the exploration of Sasuke and Sakura's relationship in a more intimate way. It could involve scenarios where they express their love and attraction more explicitly compared to the original story. These fanfics might also play with different timelines or alternate universes to create situations for their relationship to develop in a more 'spicy' way. But, again, due to the 'lemon' nature, it may involve content that some might find inappropriate, so it's crucial to approach with caution and respect for the source material.
If Sakura dies in a fanfic, it could have a huge impact on the whole Naruto -verse within that story. Her friends like Naruto would be deeply affected. Naruto might feel like he failed to protect her, just as he felt about other losses in his life. And for the medical ninja community in the fanfic, her death could be a big blow as she was a talented medic.