Important
Genymotion Desktop does not work well with virtual webcams (see Can I use OBS virtual camera with Genymotion Desktop?). The use of virtual or loop cameras is not recommended, nor officially supported.
For your webcam to work properly with Genymotion Desktop, it must support the UVC standard (USB video device class).
Here is a list of webcams supporting the standard: http://www.ideasonboard.org/uvc/
This is the reference list regardless of your environment (Windows, macOS, Linux).