There is a basic legal problem with trying to outlaw cartoon child porn.
This is best described by the “stick figure test”. Draw two simple standing stick figures.
Caption them as two adults having a conversation about politics. Quite legal. Caption them as two young children having sex, even if they are not touching, and it is child pornography. The porn is in the text, not the pictures.
Cartoon characters can have adult features, child features, anthropomorphic animal features, even mechanical features, that are vague enough to be subjective, and can even be modified by descriptions. Likewise, they can change or morph, age or become young, say one thing and do another.
The US tried banning child pornographic cartoons, but it has ended up with federal judges *subjectively* deciding cases based on their own opinions, not the law. This means that some judges will define child porn as most anything, and some rejecting real child porn as nothing.
Stick figures and explicit drawings are two different things.