Another idea is to have some of the RWBY characters transported to the world of Overlord. Ruby, with her speed and scythe skills, would be an interesting addition to the battles in the Overlord world. Weiss could use her glyphs in unique ways against the different creatures there. They might initially be confused by the new world but gradually adapt and try to find a way back home while also making an impact.
One idea could be to have Ainz Ooal Gown from Overlord end up in the RWBY world. He could be seen as a powerful new force, and his magic and strategic mind would create a lot of interesting scenarios. Maybe he'd form an alliance with one of the academies, or be seen as a threat by Salem and her forces.
One idea could be the characters from RWBY ending up in the world of Overlord. They might initially be confused and have to adapt to the new, more dangerous environment. Maybe Ruby could mistake some of the Overlord's minions for Grimm and attack, causing a stir among the various factions in the Overlord world.
One plot idea could be that a character from RWBY gets transported to the world of Overlord. They might have to navigate the power - hungry and often dangerous world, trying to find a way back home while also dealing with the various powerful beings in Overlord. For example, Ruby could end up in the Tomb of Nazarick and have to figure out how to interact with the Floor Guardians without getting killed.
One interesting concept could be the combination of the power systems. In Overlord, there are unique magic and abilities, and in RWBY, there are the Auras and Semblances. Fanfictions might explore how characters from one universe adapt to the power mechanics of the other. For example, how would a character from Overlord use an Aura if they were suddenly in the RWBY world? Another concept could be the cultural clashes. The different races and cultures in Overlord meeting the diverse characters and kingdoms in RWBY could lead to really engaging storylines.
One interesting RWBY Overlord fanfiction could be one where the characters from RWBY are transported to the world of Overlord. They might have to adapt to the new and often darker and more dangerous rules of that world. For example, Ruby could be intrigued by the magic system in Overlord and try to learn it while also facing the threats of the various powerful entities there.
One idea could be an Overlord crossover with Sword Art Online. You could have the powerful beings from Overlord enter the virtual world of SAO and cause chaos among the players. They might see the game world as a new territory to conquer or just a place for some interesting 'experiments'.
One interesting idea could be a crossover of different timelines within RWBY. For example, characters from the past meet the current ones and have to deal with the differences in their worlds. Another could be a crossover of different teams in unexpected ways, like Team RWBY having to team up with a rival team to face a common enemy that is more powerful than any they've faced before. And sometimes, there are crossovers that involve alternate versions of the characters, where their personalities or abilities are slightly different, which can lead to very unique and engaging storylines.
One idea could be to have the characters from 'Overlord' end up in a different anime world like 'Sword Art Online'. They could interact with the SAO characters, with Ainz Ooal Gown perhaps trying to establish his own guild in the SAO world. Another idea is to cross 'Overlord' with 'Naruto'. Picture the undead minions of Ainz in the Hidden Leaf Village, causing chaos and confusion among the ninja.
One interesting plot could be exploring the backstories of the minor characters in the Overlord game world. For example, the lives of the villagers who interact with the powerful overlord character.
One idea could be a crossover where a character from RWBY gains the powers of Dishonored's Corvo. They could use the blink ability to quickly dodge attacks in battles against Grimm. Another idea is to have a setting where the world of RWBY is affected by the plague from Dishonored, and the characters have to find a cure while dealing with political unrest.
One idea could be a crossover where The Punisher teams up with RWBY characters to take on a new, powerful criminal organization in Remnant. He could bring his unique combat skills and no - nonsense attitude to the mix.