I am not familiar with Garmin Virb Data Overlays, but I found this if it’s helpful!:
Garmin VIRB is a line of action cameras offered by Garmin, and it does have the capability to overlay data onto videos. However, the availability and functionality of overlays may vary depending on the specific model of Garmin VIRB camera you are using.
To import overlay files or customize overlays on your Mac, you can use Garmin’s VIRB Edit software. VIRB Edit is a video editing software provided by Garmin, which allows you to import and edit videos captured with Garmin VIRB cameras. You can download VIRB Edit from the Garmin website (https://www.garmin.com/en-US/software/virb-edit/).
Once you have installed VIRB Edit on your Mac, you can import your race videos into the software and explore the available overlay options. VIRB Edit provides a range of data overlays, such as speed, distance, elevation, and more. You can customize the appearance and position of the overlays according to your preferences.