The way Haya's Data Copy quirk gets used in the plot reminds me a lot of more basic 'power mimicry' stories where the main point is watching someone gather tools, but it operates with some unique constraints that shake up the usual MHA dynamics. She can't just copy anyone's power directly; she needs data, which means observation and sometimes physical interaction. That introduces a procedural, almost detective-like layer to her hero work that other characters don't have. She's not just reacting to a villain with raw strength or a clever application of her own singular ability; she's gathering intel mid-fight, looking for a specific weakness she can exploit with a copied quirk. It makes her confrontations feel more tactical and less predictable.
Where I think it most significantly impacts storylines is in team-ups and the information economy of the hero world. She becomes a living repository of quirk data, which has huge implications for analysis, training, and strategy. If she works with a team regularly, she can temporarily fill gaps in their lineup, acting as a flexible wildcard. Narratively, this lets the author explore combinations of quirks without permanently giving those powers to a character. A fight where she has to copy a portion of Bakugo's explosion alongside Tsuyu's tongue could create a completely novel attack strategy for a single, desperate moment, then it's gone. That ephemeral nature of her power set keeps her from becoming overpowered in a long-term sense, forcing creativity.
That said, I sometimes feel the story underutilizes the potential consequences of her ability. Like, what about the ethical or legal issues? If she copies a villain's quirk and uses it, is there a blurry line there? Or the personal toll of constantly having foreign quirk factors in her body? They touch on it, but mostly it's treated as a straightforward tool. It's a cool power for moving specific plots forward, especially ones involving investigation or sudden, unexpected power needs, but I wish it came with more inherent drama tied to the copying process itself, not just the application.