https://wccftech.com/how-to-download-watchos-6-beta-6-without-developer-account/

Need to download watchOS 6 beta 6 on Apple Watch without a developer account? We’ll show you how it’s done.

It’s kinda hard to believe that the sixth beta of watchOS 6 is already available for testing. Obviously, it’s something that only developers get to try out, not public beta testers. However, if you are willing to take a leap of faith and wish to try out watchOS 6 beta 6 right now, then you are in luck.