I’m very interested in what you are talking about. I don’t know anything about home brewed hydrogen. I’m going to have to jump on google I guess.
There are a handful of homemade kits you can put together for a hydrolysis unit. And if you look up “green hydrogen” you’ll see a fair amount of discussion on doing it at a power plant. But as of now there are few ready made products for the home hydrogen generation, and all of it overseas, particularly Australia. There were a couple of companies who said the were developing a home product for sale in the U.S., but I think they dropped it. (Plug Power and Panasonic)