I asked this same thing, and @Dan@Adams clarified...(at least for Adam's) they are NOT the same thing. One basic difference is in the name. Rinseless needs water to function in its intended form, WW does not. Diluting RW 16:1 will produce a Waterless Wash-like solution (and at a cheaper cost), but again, they aren't the same. The chemical components of each, such as emulsifiers, gloss enhancers, if any, etc., are different. The scents are different, too...RW is a berry scent, WW is green apple (and one of my personal favorites).
Take a quick look at the product pages for more details.
https://adamspolishes.com/adam-s-waterless-car-wash.html
https://adamspolishes.com/shop/exterior/carwashing/adam-s-rinseless-car-wash.html
I have and use both, for what it's worth.