The most popular free alternative for Mac. It acts as a virtual audio driver that allows applications to pass audio to other applications with zero latency. It is open-source and regularly updated.
Loopback is a premium macOS utility used to route audio between applications, effectively acting as a virtual mixing board. A full license typically costs $99 USD . Loopback License Key Free
If you need a permanent solution without a $99+ price tag, these open-source tools provide similar "virtual cable" functionality: The most popular free alternative for Mac