It's an OK movie until you reach the end. It was flushed down the drain. They broke the show's own rules with predictable "we are going to break them just this once" notion, which does not make sense, especially if you are paying any kind of attention to the actual continuity.
Instead of making turning 2 OFAs into a "miracle", that could at least write it off as OFA not being actually passed, since Bakugo did not consume Deku's blood. We already know that there are hints of Deku having some extra power, so temporary boost could be part of that. But even without that: how the hell did he reach 100% without breaking his body completely? And even after being damaged how come he still is able to move, when he is barely doing that while passing over OFA?
And the most stupid thing to do is make Bakugo forget about everything. They've been showing his softer side (which also does not make much sense considering his character in the main show) during whole movie and then they just kill it. I mean, this could be a groundbreaking development of the character and relationship of the 2 movie MCs: through own short experience Bakugo understands what kind of a burden this power is even for him, who is strong with far more training, and he secretly (or even openly) respecting Deku for his perseverance, at least.
And now that I am bashing it: the whole premise is not well thought-out: I understand they are heroes, but sending whole class of kids to supervise an island without at least one person to supervise (not necessarily help) them? Even when this is being done specifically, because of the current world situation? That does not make sense: they still need guidance and perhaps someone to assign more suitable roles to them, when required. I mean... Why do they send Deku, Uraraka and Froppy to find 1 kid and why are they being all sent in 1 direction? That's not how searches are done.
Involvement of League is also pointless. It's not explained at all, because it's not required. Simple "transportation" of apprehended villain Nine could work way better. Or attempt of apprehension of him. And Nine himself is poorly written: why does he want his "utopia"? What are the quirks he has? We've only seen 5 I think. His comrades have even less background as well, even though they are meant to be "focal points" as well. Could be replaced by some low-level henchmen instead.
So, writing is definitely bad here, but for the most part you can ignore that and watch it as a regular Academy show. But right in the final fight it fails at back-flip and breaks its back completely.
