Front lights compatible with a Garmin mount

This range is designed to fit onto Garmin mounts - although the design is meant to go 'right side up' as opposed to upside down I think. I have one and put it on the out front mount and relegate my Garmin 520 to a stem mount.

https://road.cc/content/review/magicshine-allty-1000-275075

I've got the moon mx light which mounts on your stem bolts. Really neat solution. Doesn't look as fancy as a k edge mount but it tidies up the bar nicely. 

Plenty of GoPro mounts available for -for instance- Moon lights, to achieve an arrangement like the picture above (I use one for a day flasher). If you definitely want a Garmin mount, consider the cheap stick-on ones you can buy on eBay and Amazon. I'm currently trusting a fairly expensive Ravemen light to such a mount: it feels welded on, and puts the light nicely in front of the stem.

Have a look at the Moon MX light/Garmin mount, that may be what you need

There's a screw in mount on the underside of these.

https://www.closethegap.cc/product/hidemybell-regular-gws/

Fit a GoPro mount there are a number of lights that will fit on a GoPro.
Here is the set up on my bike, a stem fitted mount with Wahoo on top and Fly12 on the GoPro mount.