there's also...
The early 1970's GE compact toploader. It didn't have an agitator, it had an impeller disc/plate at the bottom of the tub. I don't know how good they cleaned though? And Im not sure the turnover was all that great in these, from what I've seen in YouTube videos? Maybe someone who's used one can tell you better.
And there's also the twin tub washer that had the impeller disc off to one side, at the bottom of the washtub. And being off to the side at the bottom causes a whirlpool effect which I think pulled the clothes down, causing some turnover action. I'm not sure but I think those are Panasonic, Sanyo, or Hitachi? Someone with more knowledge can tell you which one it is for sure.