The latest version of the Wink app added this integration. After updating, in the Wink app go to "Shortcuts" and "Add shortcut." At the bottom of this screen will be an option to try making a beta voice shortcut through Google.
Click "Try it" and then choose the mode that you want to program for. Unfortunately there is not an option for custom voice shortcuts yet, but the current assortment covers Morning, Away, Cooking, Movie, TV, Party, Reading, Working, Exercise, Sleep, Vacation, Transit, Night, and Sleep modes.
|Several modes are available|
Trigger Google's voice controls with "OK Google," and when it is listening say "Activate night mode in Wink" (or substitute your desired mode). I've set Google Now to always listening when my screen is on, the process for triggering the voice command may be different depending on your configuration.
|Successfully activating Night Mode|