A crossover with Adventure Time would also be cool. Ok Ko could end up in the Land of Ooo. He might team up with Finn and Jake to battle some sort of evil force that threatens both the plaza and Ooo. They could exchange their different fighting styles, like Ok Ko's formal karate training compared to Finn's more improvised sword - fighting.
Perhaps OK KO travels to Steven's universe and is amazed by the different types of gems and their abilities. He could learn from Steven about gem culture and in return, teach Steven some of his cool fighting moves. This could lead to them going on an adventure together to help a group of gems who are in trouble.
One idea could be a crossover with another popular animated show like 'Steven Universe'. OK KO could end up in Beach City and have to team up with Steven to fight off a new type of gem - infected villains. They'd combine their unique powers, like OK KO's power fist and Steven's shield, to take on the bad guys.
The mash - up of different settings. The Ok Ko world with its own set of rules and the Nexus world which is likely very different. When combined, it creates a really unique backdrop for stories.
A possible plot could involve a gem experiment gone wrong that creates a threat that spans both universes. Steven, being an expert on gem-related things, and KO, who is always ready to save the day in his world, join forces. They meet at a neutral zone between their worlds, which is being affected by the chaos. Together, they have to find the source of the problem, which is a gem - machine hybrid that is sucking the energy from both universes. They encounter various challenges on their journey, like dealing with gem traps andobox security systems. Along the way, they also make new friends from both universes who help them in their quest to stop this hybrid threat.
In some fanfictions, OK KO could go on a journey to a different dimension. This would be full of strange creatures and new challenges. He'd have to use his wits and powers in unique ways to find his way back home while also helping the inhabitants of that dimension.
A fanfiction could center around a lemon - based competition in the Ok Ko! world. Carol and Enid decide to enter as a team. They have to compete against other characters. They come up with creative strategies, like using Carol's physical abilities to gather ingredients and Enid's knowledge to create the best lemon - based product. Their teamwork and friendship are put to the test.
Enid from OK KO and Pearl from Steven Universe. Enid is a bit of a cool, laid - back character with her own brand of strength, and Pearl is a very refined and skilled gem. They could have a great dynamic, like Enid teaching Pearl some modern - day Earth things, and Pearl showing Enid some of her elegant combat moves.
Definitely Steven from Steven Universe. His kind and curious nature would contrast well with Ok Ko's more action - oriented personality. Plus, their different powers would make for an interesting dynamic. They could learn a lot from each other, like Steven could teach Ok Ko about gem culture and Ok Ko could show Steven some new karate moves.
One idea could be an OC who has a unique power related to time manipulation. They could accidentally freeze time in the plaza and have to figure out how to unfreeze it without causing chaos. Another plot could involve an OC from a different dimension coming to Lakewood Plaza Turbo and trying to adapt to the strange rules and heroes there. Maybe the OC has a power that is considered a curse in their own dimension but could be useful in Ok Ko's world.
There might be a fanfiction where the ninjutsu from Naruto's world is introduced to the characters in Ok Ko. For example, Naruto could teach Ko how to use the Shadow Clone Jutsu, and they use it to prank the other characters in a really fun and light - hearted story.