Voicemeeter for Mac

Voicemeeter is a virtual audio mixer: it installs virtual audio devices and lets you mix and route sound between applications, microphones and outputs, which is common for streaming, calls and recording. VB-Audio provides it for Windows only.

There is no Voicemeeter for Mac with the same mixing console, so the open-source options cover parts of it. BlackHole is a virtual audio driver that passes sound from one app into another, for example from a browser into a recorder or streaming app. Background Music sets volume per app and can pause music when other audio starts. macOS's Audio MIDI Setup can combine devices into aggregate or multi-output devices, which pairs well with BlackHole for more complex routing.