>>9393530Just more hacky American thinking. You can tell thee silhouette apart with their weapons, and the better comic artists can do it with body language and faces.
Anime manages to have characters with similar body types and no one gets confused within a show. There are dozens of other differences to set them apart in terms of accessories, body language, expressions, etc.
If you must have the turtles be different body types, you can do it subtly, without making them massively different. This pitch did it pretty well, and even has Raph as slightly bigger without being absurd.
