Wear OS 2.0 does not force this and if developer does not upload standalone APK to Play Store, leaving it bundled with phone's APK as before, it will still work like in Android Wear 1.x.
Enpass didn't upload standalone Wear OS APK, so you won't see it as compatible with the watch on the web Play Store and it won't let you install it there. The only way is to open Play Store on the watch and go to "app from phone" section, but as I said before, this doesn't work right now.