William Bouguereau, Nymphs and a satyr, 1873
Bouguereau cared for composition above all else. This satyr’s legs here are like transplanted chamois legs and look kind of believable in the still image, even though they would probably look unnatural in motion. The fur coat starting halfway down the thigh also feels contrived to me (nice excuse to show the satyr's fully human buttocks!) but aesthetically it certainly works.
Elihu Vedder, Marsyas Enchanting the Hares, 1899
The legs portrayed in this picture are easy to the eye and give a good outline and balance to the satyr’s figure, but they don’t make sense from the anatomical point of view. The calves look like they have no volume and are somehow fused with the thigh. The shaggy fur isn’t enough to conceal the inconsistency, but the legs aren’t really a focal point of the picture so it’s the overall impression that matters. The figure’s outline is very similar to a common hieroglyph depicting a sitting woman, I suspect it is an actual quotation:
Even though I study my fair share of anatomy I'm not veterinarian and designing a truly consistent model would require also require the kind of 3D simulations used for big budget games and movies. In fact there are some cool digitigrade designs in games and movies (the minotaurs of Narnia come to mind) but I can't remember any instance of them exploring the full extent of the mobility which an anthro body with digitigrade legs could have, probably beacuse it's not required by the media. For them creating believable walk/run cycles is the most important thing. On the other hand a lot of anthro art is still pictures of nudes and sex scenes in which the nuances of what a limb can or cannot do are more relevant.
Carlos Schwabe, The Afternoon of a Faun, 1923
Same leg design as Bouguereau. Here the weird leg anatomy is exploited well for dramatic effect, they are supposed to look uncanny. A human in the same pose would look awkward rather than impressive.
Unknown artist, Pan and Daphnis, III-II century BC
This is one of the most believable designs I could find in ancient art and it’s similar to what is expected of realistic anthro art today. The thighs actually look like they are part human and part animal, and the legs seem to bend just like goat legs. They are also shorter than human legs compared to the torso, which would give Pan a low center of mass helping with balance (balance being the biggest issue with the idea of bipedal digitigrade legs).