On iOS 14 calling itms-watchs:// calling URL scheme opens watch app and show "Watch Face Unavailable" "This watch face is not available with your current version of watchOS". However, I used to watchos 7.02 version which is the latest one. And no Watch Face was not implemented on the application.
Use 'itms-watchs://bridge:root=GENERAL_LINK' it works fine.
For more references
https://medium.com/@contact.jmeyers/complete-list-of-ios-url-schemes-for-apple-apps-and-services-always-updated-800c64f450f