This article introduces how to change the sound output device for specific apps in Windows 10.
For example, you can configure it so that you normally want headphone output (or USB DAC output, etc.), but you want the sound from this app only to play from the speaker, or from the laptop body, or from the monitor.
In my case, with translation software called qtranslate, when playing pronunciation of English or Spanish, I wanted to output to the speaker via the monitor assuming the case when I’m not wearing headphones.
Open Settings with Windows-I, enter “app volume”, and select the sound mixer option.

You’ll see a screen like the following, so please change to your preferred settings.

In this way, you can change the sound output device for each app.
That’s all.