Hey @Helix !
I own a Google Nexus 6, I have a Magnetic mount in my car and frequently use my Anker Qi charging device.
There has been no issues (If you place them properly). I use my magnet mount just underneath the camera (which does cover the Motorola finger indentation. The Qi sensors are just below that, so it has not been an issue.
I recommend using scotch tape to test both the mount and Qi charging before placing them first.
I'm hoping @Ankerofficial will listen when we ask for a car mount Qi charger.