Change default settings for any app

Is there a way to change the default settings on a per-app basis? As an example, say I have built a Nextcloud instance with the Passwords app installed and enabled, and I want to configure the app to use my on-premises Besticon server for favicons. How can I preconfigure that setting? There are a few similar questions that have not yet been answered:

I could probably set values directly in the NC database . . . but that seems awfully dirty. Is there a standard way to do this?