win-capture-audio is described as 'An OBS plugin that allows capture of independent application audio streams on Windows, in a similar fashion to OBS's game capture and Discord's application streaming' and is an app in the Audio & Music category. There are three alternatives to win-capture-audio for Windows and Mac. The best alternative is VB-Audio VoiceMeeter, which is free. Other great apps like win-capture-audio are VB-Audio Virtual Cable (Freemium) and Virtual Audio Cable (Paid).
VB-Audio CABLE is a Windows Audio Driver working as a Virtual Audio Cable. After installing the VB-CABLE driver, a new playback device appears in the audio device list and can be set as default device. VB-CABLE can be set as the default device, just like any regular audio device.