Basically I just cut cone and cylinder shaped holes from Low-Poly Bulbasaur by FLOWALISTIK - then added a second version with a 4mm drainage hole.
The idea to adapt the model for this purpose came from Hitsman.
In my version the angles and diameters of the holes have been adjusted so that a slightly larger pot fits comfortably, without having to print a physically larger model. As a result it also uses slightly less material and prints a bit faster. The holes have been designed to remove the two sharp 'horn' protrusions from the back.
Does not require resizing, (although you can), but by default it gives you 50mm+ diameter hole for the plant pot and should be printable in less than 8 hours.
Does not require supports, but must be printed slowly - 30mm/s to deal with the overhangs on the legs, neck and back.
Two versions included - one with a drainage hole, one without - (in case you want it directly on your table without risk of it leaking out)