I Know this is a complex topic it is not possible directly in Electron.js on macOS.
I am looking for any solution where I can achieve it is using a virtual device or a aggregate device but we should be able to control it programmatically.
I have seen a few applications that are achieving it by creating aggregate/virtual device and then set that device as system default audio output when the application is in use and later restore it to the default settings.
I tried to create my own Version of Blackhole but it dose not appear in my system as a new device after installation.
Any help will be greatly appreciated.