One interesting Arrowverse OC fanfiction could be about an OC who has the power to manipulate time and how they interact with the existing heroes and villains in the Arrowverse. They might start by trying to prevent a major disaster that was foreseen in a vision.
One interesting crossover could be the Flash from Arrowverse meeting Quicksilver from the Avengers. They could have a race to see who is truly the fastest. Another could be Green Arrow teaming up with Hawkeye for an archery - based mission where they share their different techniques and arrow - making skills.
One interesting concept could be the different team - ups. For example, Batman might team up with Green Arrow in unique ways that we don't see in the regular DC universe. Maybe they combine their detective skills to solve a complex mystery that spans across both Gotham and Star City.
One idea could be a story where characters from different Arrowverse shows team up to fight a new, powerful villain from a different dimension. For example, Oliver Queen from 'Arrow', Barry Allen from 'The Flash', and Kara Danvers from 'Supergirl' could combine their skills and powers to take on this threat.
Maybe the Flash could visit the MCU. He could race against Quicksilver. It would be a really cool showdown of speedsters from different universes. And then the Flash could get involved in an MCU - level threat, like Thanos' invasion but in a different timeline. He could use his speed to try and steal the Infinity Gauntlet from Thanos, creating a whole new plotline for a fanfiction.
A cool concept could be a crossover where the technology in Gotham and the magic in Star City somehow get mixed up. Batwoman, being more used to high - tech gadgets, and Arrow, who has some experience with magic - related threats, have to combine their skills to set things right. For example, a device that was supposed to enhance Batwoman's suit ends up being enchanted by magic from Star City, and they need to figure out how to fix it and stop the villain who caused the mix - up.
One idea could be a crossover where characters from Arrowverse and Young Justice have to team up to stop a multiverse - threatening villain. For example, Green Arrow and Nightwing leading the combined forces.
One idea could be a crossover of characters from different Arrowverse shows on Earth X. For example, having Barry Allen from 'The Flash' team up with Kara Danvers from 'Supergirl' to fight against the evil regime on Earth X. They could use their super - speed and super - strength respectively to take on the powerful foes there.
One idea could be that the Winchesters end up in Star City and team up with the Arrow to fight a demon that is using technology to cause chaos. Maybe the demon has possessed some of the tech - savvy villains in the Arrowverse.
Well, in some 90210 oc fanfiction, there are stories about new characters trying to fit into the glamorous world of 90210. They might face challenges like dealing with the rich kids' cliques or finding their true love in this posh setting.
One interesting crossover could be the characters from Riverdale getting involved in an Arrowverse - style crisis. For example, Archie could find himself in Star City during a meta - human attack and team up with Green Arrow. The contrast between the small - town drama of Riverdale and the high - stakes superhero world of the Arrowverse would create great storylines. Another possibility is Betty and Veronica using their wits and resources to help the Arrowverse characters solve a mystery that has both normal and super - powered elements.