Like anything else My Hero Academia related the upcoming film My Hero Academia: Two Heroes has a lot of hype behind it. The animation looks great - All Might's weird eyes aside - and the story delves into the Number One Hero's past, whilst also focusing a bit on Midoriya. Excitement aside, most fans were expecting the film to be fun but non-canon since most shonen anime movies aren't.
Of course, that trend started breaking when films like Dragon Ball Z: Battle of Gods and The Last: Naruto the Movie actually started adding lore and important character progression to their series' respective canon. It looks like Two Heroes will be in the same boat as creator Kohei Horikoshi says that the movie is tied into the manga.
During an interview with Toho Cinematic Magazine (translations from @aitaikimochii), Horikoshi revealed that he always wanted to tell a story about All Might's past but felt that the manga had progressed so much that it would feel unimportant. This movie gave a good reason to delve into it and so he did, hence why Horikoshi considers it canon.
Horikoshi actually does incorporate moments from the anime into the manga if he feels that it adds to the character, including Endeavor's blue flames. It's nice seeing him weave cool bits from the anime into his manga, making them feel canonical to fans of both entertainment mediums.
My Hero Academia: Two Heroes hits theaters in the US on September 26 and October 2 if fans want Japanese voice acting. Those looking forward to the English dub can watch it on September 25, 27, and 29.
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