https://wccftech.com/download-watchos-6-beta-2-without-developer-account/

watchOS 6 beta 2 is now available for download and you can install the latest update without a developer account too. Here’s how you do it.

iOS 13, macOS Catalina and tvOS 13 will be available as public beta downloads next month. watchOS 6, on the other hand, won’t be. The reason for this highly likely the instability issues the software goes through while it’s in beta. If something goes wrong, there’s no way you can fix it all at home. You have to take your Apple Watch to Apple itself for it.