Say WHAT? That's exactly what I'm saying. An Xposed modules was release that does just that. Enabling it will allow you to just do that.
As long as you have the search bar on your screen it will work as it should and you'll be able to initiate any command you want. As the name implies from the screen capture it's called "Ok Google for 3rd party activities".
There's really nothing more to it than that! Why not head over to your Xpose installer on your phone and try it out for yourself?