I agree his legs look puffy and swollen- the back right most noticeably.
And his feet are so short! I've never seen feet so short- just the rears the fronts look okay to me. I think the way he is standing and possibly even the inflammation could be due to uncomfortable feet in the back, or a symptom of standing that way to alleviate it.
Actually as I look at him longer... his stifles are very low, throwing off that nice triangle. While his hip slope is okay, that stifle puts his hock at that angle and creates his sickle hocked-ness. I wouldn't know if any farrier correction could help that.