In southern Sumatra hybrids came into being, tradition asserts, as the results of assaults on women. Families among the Betsemah are supposed to be of orang pendek descent. One story tells of a man who kept an orang pendek as a mate and produced a number of children.
All this, of course, is legend. Whether such hybrids would be possible is questionable, to say the least.
Incidentally, there are also traditions of humans interbreeding with yetis. There is actually a word for the hybrid produced by such a union. It is gyad.
In Africa there is a belief that certain men mistake female gorillas for beautiful women and mate with them. The resultant offspring are fierce hybrids. I am not quite sure how you would mistake a female gorilla for a beautiful woman, but then again, beauty is in the eye of the beholder.