Create shortcut combos on Android Wear
Button Launcher is a completely free software for Android Wear 2.0 that allows you to define what apps will be launched based on up to two button press combination.
For watches with only single (primary/home) button, there are only two shortcuts to set. The first is just long press that primary button followed with no other button press (within a configured timeout), the second are two long presses of primary button in a row.
Watches like Huawei Watch 2 with 2 hardware buttons allow for 8 different shortcuts.
More info: https://forum.xda-developers.com/android-wear/development/app-button-launcher-button-shortcuts-t3757005