One interesting take could be that his death is a heroic sacrifice during a battle against a dark wizard. He might throw himself in front of a powerful curse to save his family or friends. This would show his growth from his once rather rigid and self - centered self to a selfless hero.
In a more tragic fanfiction, Percy could die from a misunderstanding. For example, he could be mistaken for an enemy by his own side during a chaotic battle. His last moments could be filled with regret for the time he wasted being estranged from his family, and his death would then be a symbol of the futility of family feuds.
One possible scenario could be that Percy dies heroically in a battle against dark wizards. Maybe he sacrifices himself to save his family or a group of innocent people. Another could be that he succumbs to a mysterious and incurable magical illness that has been plaguing the wizarding world. He might have been researching a way to stop it but in the end, it gets the better of him.
In some fanfictions, Percy Weasley may be depicted as a Death Eater, but this is a departure from the original canon. Fanfiction allows for creative reinterpretations, and some authors might explore this dark turn for his character to add drama and new plotlines.
It would be a huge blow to the Weasley family. They would be filled with grief and guilt, especially if they had any unresolved issues with Percy before his death. For example, if they had been on bad terms due to Percy's past actions at the Ministry. His death might make them more determined to fight against the dark forces, seeing it as a way to avenge Percy.
A common theme is redemption. Since Percy had his issues with his family in the original series, his death could be seen as a way to fully redeem himself. He could die protecting his family, which would be a powerful way to end his character arc.
A third plot could revolve around Percy's family relationships. He could be feeling overshadowed by his more popular siblings. So, he decides to prove himself in a different way. He enters a magical competition that tests not only magical skills but also strategic thinking. Along the way, he learns to appreciate his family more and they start to see him in a new light.
A common plotline is them working together to solve a mystery within Hogwarts. For example, in some fanfics, they might be trying to figure out who is behind a series of strange magical occurrences in the school.
Perhaps there could be a time - travel plot where Hermione and Percy are sent back in time together. They have to rely on each other to get back to their own time. During this adventure, they see different sides of each other. Percy sees Hermione's quick thinking in a completely different context, and Hermione sees Percy's loyalty to his family and friends in a new light, which could lead to a romantic relationship.
Maybe in the fanfiction, there's a situation in a collapsing wizarding building. Fred is trapped under some rubble and Percy, using his skills and knowledge of magical architecture, manages to find a way to free Fred. As they escape, they start to realize how much they've missed having a proper relationship with each other, and Percy makes a vow to always be there for Fred.
One reason could be to add more conflict within the Weasley family. Percy was already somewhat of an outcast in the family due to his loyalty to the Ministry. Turning him into a Death Eater would intensify that divide.
One interesting fanfiction could be about their adventures together in the Forbidden Forest. Maybe they discover a hidden magical creature that no one has ever seen before. They would have to use their combined skills and knowledge to figure out how to deal with it.