Audio support in macOS VMs is currently only possible by passing through a simple USB audio device from the host, which is cumbersome 😓
I have a possible solution I'm researching which is to enable VirtIO-SND in the macOS guests. It's unclear to me how complete macOS Virtio-SND support is across macOS versions, so this may only be available in the recent releases and if this idea even works at all 😁