Perhaps there could be a time - travel mishap where a current Hogwarts student ends up in the Marauders' era. The Marauders then have to figure out how to send the student back while also protecting them from the dangers of their time, like the presence of Death Eaters - in - training and the looming threat of Voldemort.
Another plot could involve the Marauders getting involved in a mystery that is plaguing Hogwarts in the present day. They use their old - school pranking skills and knowledge of the castle's secrets to solve it. They might have to team up with some of the current Gryffindor students who remind them of themselves when they were young.
A plot could involve a group of Hogwarts students accidentally ending up at Ilvermorny and having to adapt to the new school's rules and culture while also trying to find their way back home. It would be a story of discovery and friendship as they interact with the Ilvermorny students.
One idea could be Riley and her friends from Girl Meets World somehow end up at Hogwarts through a magical portal. They could be sorted into different houses and have to navigate the challenges of Hogwarts life while also bringing their own unique personalities from Girl Meets World. For example, Riley's positive attitude might clash with some of the more traditional Hogwarts ways at first.
A possible plot for Marauders Afterlife fanfiction is that they are in a sort of limbo where they can observe the lives of their loved ones. James could watch over Harry and try to influence him in small ways. Remus might find a way to comfort Tonks from the afterlife. And they could all be working towards a way to return to the living world for a short time to give important messages or help in a great battle that's about to happen in the wizarding world.
One idea could be exploring the Marauders' time at Hogwarts in more detail. For example, showing how they formed their friendship and the pranks they played on Snape that weren't in the original books. Another plot could be a time - travel fanfiction where a character from the future goes back to the Marauders' era and tries to change certain events. Or perhaps a fanfiction where the Marauders have to deal with a new dark threat at Hogwarts that no one else is aware of.
Sirius Black is often really popular. His rebellious nature and his complex backstory make him a very interesting character to explore in this kind of fanfiction. He can be shown having interactions with new characters from the modern Hogwarts era.
Perhaps in the fanfiction, Hogwarts decides to send a group of students to study the Muggle world up close with the Dursleys as their hosts. But what if the Dursleys are secretly working for a dark wizard who wants to use this opportunity to infiltrate Hogwarts? That would be a huge plot twist.
Well, you could have an OC who is a half - blood trying to keep their identity a secret. The Marauders could accidentally discover it and help the OC deal with the potential consequences. Or an OC who is a seer and has visions about the future of the wizarding world during that time, which could include the rise of Voldemort. The OC could then try to enlist the help of the Marauders to prevent it. Also, an OC with a time - traveling device that malfunctions and lands them in the Marauders era, and they have to find a way to get back while interacting with the Marauders and other characters.
One idea could be Naruto being a transfer student to Hogwarts. He might use his ninja skills in the wizarding world, like using his speed to be great at Quidditch. Another could be that Naruto discovers he has magical powers in addition to his chakra, and he has to learn to balance both. And perhaps he makes friends with Harry Potter and they teach each other their unique skills.
One interesting plot could be Harry time - traveling and getting to join the Marauders on one of their pranks at Hogwarts. He might learn some new spells and mischief - making techniques from them.
Another plotline could involve Petunia getting involved in one of the Marauders' adventures by accident. Maybe she stumbles upon them while they are exploring a secret part of Hogwarts and has to work with them to get out of a tricky situation.