You can use OBS with Loola by installing a virtual camera and virtual audio devices.
After installing the plugins, simply select the virtual cameras as the video source to Loola.
OBS doesn't have a virtual camera plugin on Mac. In order to get virtual camera in Mac, you will need to use CamTwist.
The idea is to capture the OBS video in CamTwist, and then select the CamTwist virtual camera in Loola.
Please see following guide for detailed setup instructions:
Please see the CamTwist FAQ on how to set the CamTwist webcam driver resolution:
If you run into any issue, the following thread may help: