Lanefan
Victoria Rules
Can you truly purchase them, though, to actually own; or just rent them for as long as the site stays up and-or is willing to host the material?Roll20. Fantasy Grounds. D&D Beyond. And once upon a time d20 Pro.
All of those have WotC digital products that are not in PDF file format. All of them have digital products that you can purchase as products. Do I really need to link you to the stores?
Renting is not purchasing.