Fifty years ago, much because the Nazis were considered right-wing, the U.S. eugenics movement was often called a right-wing phenomenon. Today, many conservative writers are calling it a left-wing or progressive or whatever thing. I think the truth may be that too many groups had a hand in it to call it anything but government overstepping its bounds.
Government overstepping its bounds is always left-wing, because tyranny is left-wing.