Perhaps a fanfiction could focus on the relationship between Peter B. Parker and Miles Morales. What if Peter B. Parker decides to stay in Miles' universe for a while to mentor him more intensively? They could face some local villains together, and in the process, Miles learns more about the responsibilities that come with being Spider - Man from Peter B. Parker's experiences.
One idea could be exploring the different Spider - People's home universes in more detail. For example, showing what Miles Morales' daily life in his universe was like before becoming Spider - Man. Another could be a team - up between Miles and an older, more experienced Spider - Person from a different universe to face a new and powerful villain.
A plot idea might be that there's a glitch in the multiverse that causes some of the Spider - People's powers to mix up. So, they have to figure out how to control these new, combined powers while also dealing with a threat that's exploiting this chaos. This could lead to some really fun and creative action scenes as well as character development.
One idea could be exploring the backstories of the different Spider - People in more detail. For example, how did Peni Parker really come to terms with her role as Spider - Woman in her own dimension. Another could be a crossover within the Spider - Verse, like what if Miles Morales and Gwen Stacy teamed up to face a new villain that was causing chaos across multiple dimensions.
One idea could be exploring the backstories of the different Spider - People more in - depth. For example, Peni Parker's relationship with her father and how it influenced her becoming Spider - Woman. Another could be a story where all the Spider - People have to team up against a new villain that is specifically targeting their multiverse connection. Maybe a villain who can disrupt the portals between their worlds.
A cool plot could involve a young Peter Parker from a universe where he got his powers much later in life. He ends up in the main Spider - Verse and has to learn quickly from Miles and the other Spider - People. They could all work together to stop a symbiote - like entity that is infecting different versions of Spider - Heroes. It would be interesting to see how this inexperienced Peter copes with the situation and how his different perspective might help solve the problem.
Maybe a fanfiction where all the Spider - Men and Women from different spider - verses team up to fight a common enemy that threatens all of their universes. It could be a powerful cosmic entity that is consuming the multiverse, and they have to combine their unique skills and knowledge to stop it. This would allow for a lot of cool interactions between the different characters.
Another plot could focus on a young Gwen Stacy from a different universe who stumbles into the main Spider - Verse. She has to learn how to control her powers while also dealing with the fact that in some universes, her counterpart didn't survive. This would add an emotional depth to the story as she tries to find her place and make a difference.
One idea could be a story where Miles Morales has to team up with an alternate version of himself from a dimension where he never became Spider - Man. They have to overcome their differences and learn from each other to stop a new villain that is threatening all the spider - verse.
A great plot twist could be that the main villain turns out to be a seemingly innocent character from one of the dimensions. For example, a friendly neighborhood Spider - Man's sidekick who has been secretly manipulating events all along to gain ultimate power in the spider - verse.
You could write a fanfiction about the origin of the Spider - Verse itself. Maybe it was created by a super - intelligent spider from a far - off dimension who wanted to bring together all the possible versions of Spider - People. Or perhaps a story where a new Spider - Person emerges in a dimension that has never had one before and how they adapt to their new powers and the knowledge of the Spider - Verse. Also, a story about the villains teaming up across the dimensions to take on all the Spider - People at once would be cool.
One idea could be exploring what would happen if Miles Morales had to team up with an alternate version of himself from a dimension where he didn't become Spider - Man. Maybe in that dimension, he became a villain instead. Another idea is to focus on Gwen Stacy's story more, like her adjusting to life in a new dimension where she has different relationships with the other Spider - People. You could also write about a new villain that emerges specifically targeting the multiverse of Spider - People and how they all come together to stop it.
For an Into the Spider - Verse crossover fanfiction, how about a crossover with the Teenage Mutant Ninja Turtles? They could fight together in the sewers of New York against a common enemy like the Foot Clan. Another possibility is a crossover with Hellboy. Spider - Man and Hellboy could combine their powers to defeat a demon that's causing chaos in the city. And a crossover with the Power Rangers would be interesting too. The Rangers' teamwork and their zords could be combined with Spider - Man's agility and web - slinging abilities to take on a huge monster.