How to sign APK on Android Studio even with non-translated strings?

The cleanest way to solve the problem is to disable Lint checks of missing translations for release builds only.

To do so add “disable ‘MissingTranslation'” to your build.gradle file as shown below:

android {
    buildTypes {
        release {
            lintOptions {
                disable 'MissingTranslation'
            }
        }
    }
}