Son of the White Mare
Fehérlófia (original)
The story’s main character is Fehérlófia, who is a man with superhuman power. He is born as the third son of a horse. He listened to old tales, mostly about the Forefather and the end of his reign, caused by evil dragons.
Starring György Cserhalmi, Pap Vera, Gyula Szabó, Mari Szemes, Ferenc Szalma, Szabolcs Toth
Watch "Son of the White Mare" from streaming services vimeo-vimeo-free, Kanopy released in 1981. It's a fantasy and animation movie, and has a rating of 7.8 out of 10 from Imdb which is usually fine for this kind of movie.