which document cameras are compatible with catalina

The odds of anything saying it supports Catalina are slim. Maybe next year.

As long as it just outputs video in a standard way, like over HDMI, then it should work with any macOS.

If it requires you install software to make it work, then you will likely have problems no matter which macOS it supports.

Those companies hire developers to write software for Windows, then try to convert it into a method that works the same on a Mac. Since that is hardly ever possible, they develop system hacks to make it work. Those often break when you update your OS.

What year model is your MacBook Air? It should have a mini-display port, thunderbolt port, etc. and there HDMI adapters available that let you connect your MacBook Air to an HDMI device.

What is a "document camera"?

Thanks, I was not familiar with the term.

I looked it up a bit on amazon, and quite readily found models that mention mac compatibility.

Luis Sequeira1 wrote:

What is a "document camera"?

Document camera = digital overhead projector

https://en.wikipedia.org/wiki/Document_camera

And I would think any such device would support HDMI or format that macOS can handle.