I don't see a horse resemblance either. But, I have heard that images of Akhenaten, like the one on the DomainOfMan home page, were meant to be viewed from below (by his "inferior" subjects). The photo I took was made at the Luxor Museum in Egypt and probably is not a perspective that would have been realistic in the original setting.
Also, many statues of Akhenaten show him with feminine features. The measurements of his son Tut were 31-29-43(inches). Tut probably inherited this pear-shaped figure from Akhenaten, his father. Such features may have actually been used to make a comparison with the original god Atum, who it seems had both male and female qualities. It is doubtful that Akhenaten possessed both male and female genitalia. And it is possible only to speculate about his sexual preferences.
Of course homosexuality was not unknown at this time. For example, we have the scandalous Biblical account of Hatshepsut (Absalom) laying with all of David's harem women. Although homosexuality was made a taboo among common people, I suspect it was quite common among royalty. (This is another case of "do-as-I-say-not-as-I-do".)
© Charles N. Pope, US Library of Congress. All rights reserved.