A really cool plot would be Scorpius time - traveling to the time when Hogwarts was first founded. He could witness the creation of the four houses and the early magic that was used to build the school. He might even get involved in some sort of power struggle between the founders. And his actions in the past could lead to changes in the way magic is taught at Hogwarts in his own time.
Perhaps Scorpius travels back to the Triwizard Tournament era. He gets involved in the events and tries to use his knowledge from the future to stop Cedric Diggory's death. He might also find himself in the middle of the mystery surrounding Harry Potter's name being entered into the Goblet of Fire and end up uncovering secrets that were long buried. And he could form an unlikely friendship with a young Hermione Granger.
One idea could be a story where Scorpius discovers a long - hidden family secret that Draco has been trying to protect him from. It could involve some dark magic from their family's past.
One idea could be that they travel back to the time of the founders of Hogwarts. They might accidentally change something small that has a huge impact on the present day. For example, they could prevent one of the founders from making a key decision about the sorting hat, which then changes the way students are sorted in their time.
One interesting plot idea could be that Harry teaches Scorpius advanced defensive magic. Since Scorpius is a bright young wizard, Harry sees potential in him and decides to pass on some of his own unique skills. Another could be Harry teaching Scorpius about the importance of friendship across house divides, using his own experiences with Ron and Hermione as examples.
One plot idea could be that they are paired for a school project at Hogwarts. At first, they are hesitant because of their families' past rivalries. But as they work together, they discover they have more in common than they thought. For example, they both have a love for magical creatures. They start to form a friendship that slowly blossoms into something more, like a budding romance. This would be a sweet and slow - burn kind of story.
There could be a fanfiction where Scorpius and Draco go on a magical adventure together. Maybe they discover an ancient magic that was lost for centuries and have to keep it a secret from the wizarding world. This would explore their relationship as father - son and their courage in the face of danger.
Perhaps Scorpius has a rare magical illness that only Hermione, with her extensive knowledge and unique approach, can attempt to cure. As she delves deeper into finding a cure, they discover they have more in common than they thought. They might also face opposition from the wizarding community due to their different backgrounds, but their relationship grows stronger in the face of it.
Rose Granger - Weasley could also be a sidekick. She is intelligent like her mother Hermione. In a time - travel scenario, say when they go back to the Goblet of Fire times, she could use her smarts to figure out the complex magical rules and traps. Scorpius, with his knowledge of how things are supposed to turn out, could work with her to change the outcome for the better, like preventing some of the more dangerous tasks from being so deadly.
One idea could be exploring the relationship between Draco Malfoy and his parents in a more in - depth way. Maybe showing how they influenced his actions during his time at Hogwarts. Another could be a prequel - type story about how the Malfoy family came to be so wealthy and powerful in the wizarding world. And a third could be a story where a Malfoy family member has to choose between loyalty to their family's dark past and a new path of light.
Another idea is that Draco travels back to the time of the founders of Hogwarts. He could interact with them and gain a new perspective on magic and the wizarding world. Maybe he would learn some ancient spells that were lost over time and use this knowledge to his advantage when he returns to his own time.
There could also be a story where they are paired up in a magical dueling tournament. At first, they have different strategies and struggle to work together. But as the tournament progresses, they learn to combine their strengths and in the process, form a deep bond that goes beyond just being competitors.