What power haven't appeared in comics?
I saw that you were the person who replied and immediately became panicked and drew a blank. I'm gonna have to think hard before answering because I know whatever I post, the person with the encyclopedia-like knowledge of comics is gonna be like "Nah, here's just the first three which come to mind that already do that," lol.
Okay, so after going through the list of characters with quirks on a wikia, most are things that, while implemented differently in X-books or Marvel books, still kind of lead to the same result.
Like, The Hulk gets stronger when mad, while there is a MHA character that gets stronger when embarrassed. Same thing really, I guess; it just gets to the end result in a different way. Though I wouldn't be surprised if there was an obscure comic character that also flashes his junk at people to get stronger.
Or someone like Kosei Tsuburaba exhales his breath to solidify air and create walls or platforms, but that's just the Invisible Woman's force fields with more steps. I just read through the Joint Training Arc last week and thought Class 2B had more unique powers but I guess not.
Anyway, I've narrowed it down to so far to the following (and I fully-expect to still be wrong):
-Nirengeki Shoda, Class 2B alias Mines, has the quirk Twin Impact.
Twin Impact allows the user to, at the site of any initial impact, create a second impact remotely and at their discretion. The second impact will be many times stronger than the initial one. It can be used on objects or on people.
And that's it. I was gonna say Moonfish and his quirk Blade-Tooth's ability to grow his teeth out and reshape them into weapons or stilts to carry him aloft. But hell, Doctor Octopus gets the same results from his metallic tentacles without being gross. And Iceman can do the exact same thing as Moonfish only with ice instead of teeth.
So yeah, I was pretty wrong. Some powers may be implemented or generated differently by a lot of MHA characters but they are still doing essentially the same things a lot of Marvel characters have always done.