OK, so I've installed iOS 12 on my iPhone 8, and watchOS 5 on my Apple Watch series 3, everything is paired and set up.
I have created a custom shortcut on my iPhone with the new Shortcuts app. If I hold the Home button on my iPhone and speak my custom phrase, the shortcut runs successfully.
However, if I hold the crown on my Apple Watch, and speak the same custom phrase, Siri just says it doesn't know this command.
Did I forget to configure support for this? I can't seem to find any settings for this, nor does it seem that I should install Shortcuts on the watch itself.
I've checked in the shortcuts app itself, in settings, in the watch app with the settings for the watch, etc.
Or perhaps Apple did not implement support for this (yet)?