Aren’t there non-LEGO minifigs of SU already? Not to mention Pops?
The problem with most of the toons in OP’s pic is they’re drawn in ways that don’t translate into 3D well. As much as I love Ed, Edd ‘n Eddy there is no way decent action figures can be made for the series with how amorphous their designs are in general (not even taking into account the change in art style over the years it was on air). Other mid-90s cartoons to the present line Dexter’s Lab, Foster’s, etc didn’t adhere to the standard art designing where the subject can be drawn at any angle and instead have some Picasso-esque designs that make 3D representations look horrific. Just google the Regular Show figure of Rigby to see what I mean.