Well, in the 'Harry is sent to Azkaban' fanfic, he could discover some dark secrets within the prison. There might be a hidden plot against him or the wizarding world that he uncovers while in Azkaban. And his time there could change his character, making him more cynical or determined to fight the system that wronged him.
Well, it could be that Harry is sent to a future time in 2110 for a top - secret mission. Maybe he has to deal with some advanced technology that he doesn't understand at first. He might encounter new forms of magic or threats that are unique to that time period.
There could be new types of magical creatures that have evolved or been discovered by 2110. Harry might interact with them, and they could either help or hinder his mission.
It could center around the changes that occur in the wizarding world during a particular summer. For instance, new spells could be introduced, or there could be a shift in the relationships between different magical families. It might also be about how the Hogwarts students adapt to these changes when they return to school after the summer.
He would have to learn to adapt his magic use. In medieval times, magic was often associated with the devil or dark forces. Harry would need to be careful not to draw too much attention or he could be in danger. He might also have to find new ways to communicate, as the language and culture were very different.
He might use his magic in ways that would shock the people of medieval times. For example, his ability to conjure fire could be seen as either witchcraft or a great power from the gods. His knowledge of spells could also give him an advantage in battles or in protecting himself from the harsh medieval environment.
In this fanfic, Harry is the main focus as he's the one sent to Azkaban. However, other characters would also be important. The guards at Azkaban, the Dementors, would be key figures as they would be the ones constantly menacing Harry. Then there are the Ministry of Magic officials who were involved in sending Harry there. Their motives and actions would be crucial elements in the story.
For sure Harry is there. But there could be new characters introduced. Maybe a foreign wizard who has come to Hogwarts for the summer and joins Harry in his training. The Weasley family could also be involved. Mrs. Weasley might be sending care packages to Harry during his training. And Mr. Weasley could be sharing some of his knowledge about the Ministry of Magic's regulations regarding certain types of training that Harry is doing.