See like the thing is I don’t think Ochako is like head over heels in love with Izuku like I’ve seen some people saying. Both Mina and Yuuga have said something along the lines of “you love him” but I don’t think it’s that deep. Do keep in mind Izuku and Ochako have only known each other for four months, give or take a few weeks, and I don’t think that’s enough time to really fall in love with somehow.
That’s not to say there isn’t any feeling there, but I don’t think it’s love. I think it’s more of an admiration crush than anything else.
An admiration crush mixed in with a want to be like him, like Toga said.
Cuz like, she’s seeing Izuku, who was already quite amazing, continuously improving, and there’s this selfish want to do the same, because she wants to be like him: a brave, smart, instinctively heroic person.
I’ve seen some people say that Ochako was jealous in some of the panels of the last few chapters, like this one for instance
Her face is more solemn, or sad. It could be considered jealousy, but jealousy is usually associated with a feeling of dislike. Here, I think it’s more that she’s envious of how much Izuku, and everyone else, is improving and developing since she hasn’t made any notable progress. It’s not just shown with Izuku and Iida either.
She looks the same when the other girls are talking about their special moves. Reserved and quiet.
So that’s why when she says ‘no no, it’s not like that’ in response to being told that she’s in love, I don’t think she’s just outright denying any feelings. I think she means that she wishes to be improving at the rate that everyone, including her maybe-crush, is and is frustrated that she isn’t.