Another interesting concept is a robot OC that was created by a villain but has a change of heart. This robot could struggle with its programming and new - found sense of morality. It might have to hide its true identity from both heroes and villains while trying to do good in the world of BNHA.
A robot OC could also be a student in UA. It might face discrimination from other students at first because it's not human. But as time goes on, it proves itself to be just as heroic as any human student, with unique powers like being able to transform into different types of machinery for different combat situations.
One idea could be to create a villain OC who has the power to manipulate time in small increments. This could lead to really interesting scenarios in battles against the heroes. For example, they could slow down time just enough to dodge attacks and then speed it up suddenly to surprise their opponents.
One idea could be creating a robot OC that has the ability to transform into different forms inspired by the various Grimm in RWBY. For example, it could shift into a Beowolf - like form for combat situations. Another idea is a robot OC designed by a villainous character in the RWBY universe but ends up having a change of heart and joins the heroes. You could also have a robot OC that has a unique Dust - based power system, which is different from the normal ways Dust is used in RWBY.
Maybe the Knuckle Duster has a hidden backstory that the OC discovers. The OC could be on a quest to find out more about the origin of the Knuckle Duster, which could involve delving into the history of some secret organization in the BNHA world. Along the way, they form alliances with other characters and face various challenges.
Perhaps the OC is a creation of a mad scientist who wants to use Ultron's technology to enhance their own creation. The OC then rebels against the scientist's control and teams up with Ultron for mutual benefit, leading to a series of adventures where they face various challenges together, such as fighting off military forces trying to destroy them.
One idea could be that the male OC is reincarnated as a villain in the BNHA world but has memories of his past life as a hero. So he struggles between his new villainous identity and his old heroic values. Another plot could be that he reincarnates as a quirkless character, like Midoriya was initially, but he uses his past - life knowledge to develop unique combat skills. Or perhaps he reincarnates as a powerful hero's sidekick and has to deal with living in the shadow while trying to prove his own worth.
One idea could be a crossover where Naruto characters visit the BnHA world and learn about quirks. For example, Naruto might be intrigued by how different quirks work compared to chakra. Another idea is to have a character from BnHA end up in the Naruto universe and struggle to adapt to the ninja lifestyle. Maybe they try to use their quirk in a world that runs on ninjutsu and find it either very useful or completely ineffective.
The OC could be a therapist who is assigned to treat Elliot. At first, Elliot is very resistant to the idea of therapy. However, the OC is persistent and gradually breaks through his walls. As they interact more, the OC starts to understand Elliot's complex mind and the world of hacking he is involved in. This leads to a romantic connection as the OC becomes a part of Elliot's world and helps him in his fight against Evil Corp.
One interesting Robot OC fanfiction could be about a robot created for a specific mission but developing emotions and defying its original programming. It might struggle with fitting into a world that doesn't fully understand it.
First, think about the character design of your robot OC. Decide on its appearance, such as whether it's a sleek, modern - looking robot or a more clunky, retro - style one. Then, consider its powers. It could have abilities related to technology, like hacking into systems or emitting electromagnetic pulses. Next, plan out the plot. Maybe your robot OC is on a mission to find its place in the BNHA world, or it's trying to stop a new threat that targets both humans and robots.
One idea could be that the main character uses their gamer skills to level up their Quirk in unique ways. For example, they might treat Quirk training like leveling up in a game, with different quests and achievements related to mastering their power.