So I created a new world, and I was playing for a bit – until I found a desert village with these weird glitching villagers. At first, I didn't understand what was happening, I tryed to reload the world but the visuals kept the same. Then in another village, it was more clear that there were bees in the villagers heads. I entered creative and spawned some villagers, same result. Entered another world, spawned villagers, bee heads again.
 
The problem disappeared when I closed the game and restarted it, all the same villagers turned back to normal