The system-wide dark mode feature was one that users had been requesting for years, and they finally got their wish in Android 10. However, there is still room for improvement. While Google added a developer option to force all apps to turn on dark mode (even those that hadn’t been specifically updated with the feature), there is no way in stock Android to enable a forced dark mode on a per-app basis. As expected, the XDA community came to the rescue. XDA Recognized Developer Quinny899 released the DarQ app in June, letting users enable per-app forced dark mode.
It does this by using an ADB script, which has to be downloaded separately. The app now requires the user to grant it ADB shell-level permissions so that it can run the same command of the forced dark mode option without needing root.
See DarQ enables per-app forced dark mode on Android 10 without root
DarQ is an app that lets users enable a forced dark mode on a per-app basis on Android 10. It now works without root thanks to the use of an ADB script.