Some background might help further this discussion.
We have multiple classrooms that have a variety of USB cameras and microphones installed in them. I want to use a Raspberry Pi to help manage the different devices and present a single, unified USB webcam device back to the Windows computer.
The problem is that with multiple devices, faculty are unsure of which is the right device to select as a microphone or a camera in their recording, Zoom, or Skype. I want to present them with a single choice and leave the management of the various devices up to the configuration on the Pi. In some rooms there may be a simple cheap webcam, in others there might be a high end PTZ camera and an array of microphones, or a mix of all of the above.
Is such a thing possible? Or would it all be able to mix it out the HDMI port and then be something we could convert to USB from there? I'd rather have it as a USB device and avoid the extra hardware if possible.