"Wonder Wash" DIY Request

If you want "easy" it will cost in cash. If you want "cheap" it will cost you in labour
You could improvise with a bucket and a stick?

L.

Looking at the website and from the description, it may only be a large sealed bucket that is turned by hand crank fitted with a hose connection to drain and fill up.  Note that this is a manual process that you have to actually run the cycles that a normal washer does.  You fill, crank a couple of minutes, drain, fill with rinse water, rinse cycle, and drain again.

The clothes will still come out sopping wet because there is no high speed spin cycle.  You may need to get one of those old-fashioned clothes wringers/roller presses to get the water out before you hang dry.  You would have to run a conventional dryer extra long to get rid of the excess water.

You may be able to convert a 5-gallon bucket to do the job.  Or else find a small plastic pickle barrel from a food industrial supplier. Maybe a small cement mixer drum and apparatus.  It should have some bumps or agiator fins on the walls to help circulate and wash the clothes.  You could add some thick plastic or aluminum fins and rivet them to the walls.  Some epoxy would seal it up. There are various methods to attach a drainspout to a barrel.  Unless you find some things that will work, the materials cost may outweigh what the actual product is selling for.  Good luck.