Another plot could involve Harry being seild away accidentally during a magical experiment gone wrong. He could end up in a different time period, like the past of the wizarding world. There, he might interact with the founders of Hogwarts, which would be really interesting as he could learn about the origins of the school and the magic they used. He would also have to find a way to get back to his own time.
Hermione would be a common character. She would likely be very determined to find Harry and bring him back. She might use her vast knowledge of magic and research skills to track him down.
One possible plot could be Percy's struggle against the power that seals him away. Maybe he has to find a way to communicate with his friends on the outside to get help. Another could be the discovery of the true motives behind his seclusion.
A really cool plot could be Harry getting the power of mind - reading. This would give him a huge advantage in his fight against Voldemort. He could read the minds of the Death Eaters to find out their plans and secrets. However, this power also has its drawbacks. He might accidentally read the minds of his friends and learn things they don't want him to know, which could strain his relationships. Also, it could be overwhelming for him to constantly hear the thoughts of everyone around him in a crowded place like Hogwarts.
In this type of fanfiction, there could be a plot where Harry is hypnotized during a Quidditch match. The opposing team might have used some dark magic to hypnotize him so that he would lose the match. However, his broomstick, which has a special bond with him, could start to resist the hypnosis on its own. Meanwhile, his teammates realize something is wrong and try to protect him from further harm while also looking for a way to break the spell.
Another possible plot is that Harry, realizing the importance of fitness in his fight against Voldemort, decides to train his body as well as his magic. He might go on adventures in the Forbidden Forest, running from dangerous creatures and climbing trees, which not only improves his fitness but also his survival skills.
Maybe Harry uses a forbidden spell in the Gryffindor common room and gets caught. As a result, he's grounded and not allowed to participate in the upcoming wizarding event. He then has to find a way to make it up to his housemates.
Another plot could involve Harry's friends' reactions. Some might be very accepting and helpful, while others could be confused or even act differently towards 'her'. This could lead to some interesting character development and story arcs for both Harry and his friends.
In some fanfictions, Harry might get out of town to escape the constant danger and media attention. He could end up in a small, peaceful village where he learns new, non - combat magic skills and forms unexpected friendships.
Another plot could be that they run away to escape the chaos and danger at Hogwarts during a particularly bad time, like when Voldemort is really tightening his grip on the wizarding world. They set out to find allies outside of Hogwarts, like some old and forgotten wizarding families, and together they form a resistance against Voldemort.
In some 'harry gets summoned to another world fanfiction', a cool plot is that Harry gets summoned to a world where magic is scarce. He has to figure out how to use his existing magic knowledge to help the people there discover or regain their magical abilities. Or perhaps he's summoned to a world where there are mythical creatures he's never seen before, like giant talking birds or shape - shifting foxes, and he has to form alliances with them to survive.