INTERESTING QUIRK-PEOPLE TO KEEP IN MIND:
1)MOMO: Her quirk is said to convert lipids into other objects by changing their molecular structure.
-First of all, the exchange rate for the objects she makes would be too high, especially for her thin body, so best to over look that for now.
-Lipids can mean any Organic Compound that does not dissolve in water, including body fat, oils, waxes and even HORMONES. This kind of Conversion seems way too dangerous for any person to make, so assume that she only converts her Body Fat.
-Now, if she overused her quirk and her body fat is completely depleted, would some other part be disintegrated for the Conversion? If it affects her Muscles or Internal organs, it could very easily lead to death. so be careful if you are writing a Plus Ultra moment for her.
2)KAMINARI DENKI: An author called HolyJoker wrote an incredible fanfic on this character and the flexibility of his abilities, I recommend you check it out if you please.
If you want some creativity for this character. some other-rather farfetched-abilities that i could think of for this character are written below:
-Since the human body transfers electric signals for all bodily functions through nerves, you could fry their nerves and leave the immobile.
-Since memories are just waves of electric signals traveling through the Brain, they can be altered/erased/fabricated(this is rather impossible in know, since the computing power and precision required for this is impossible for highly complex machines, let alone humans, so maybe make it seem like an accident)
3)MANGA FUKIDASHI:1B Student who can materialise words into existence
-A prime example of the sheer Unpredictability and ridiculousness of the world and the Quirks in it.
-Some combinations of letters spoken in a specific order to make them fit like puzzle pieces could be interesting.
4)SHIHAI KUROIRO: His Quirk allows him to merge into anything black or dark(including shadows).
-With additional training he can even move the objects(if they are movable in the first place like humans, vehicles, etc), kinda like Shikamaru from Naruto
-He can hide in shadows and be transported in them, but the shadow needs to be dark and constant(a vehicle's shadow could work best)
-he could get under a fast moving vehicle and guide it to disaster or make him op and control other's shadows.
5)REIKO YANAGI AND YUI KODAI: Potential for a cool Plus Ultra moment.
6)MEZO SHOJI: Mature, Empathetic, Gentle and doesn't hesitate to help others or sacrifice himself
-Comes from a town which still holds prejudice towards people with Quirk-altered bodies but still wants to protect people. Doesn't have material attachment or hold grudges.
-Wears a mask because a small girl cried when she saw him and he doesn't want that to happen again
COULD MAKE FOR A VERY INTERESTING CHARACTER