Locale fallback

nuxt-i18n takes advantage of vue-i18n ability to handle localization fallback. It is possible to define a single fallback locale, an array of locales, or a decision map for more specific needs.

nuxt.config.js

modules: [
  'nuxt-i18n'
],

i18n: {
    vueI18n: {
        fallbackLocale: 'en',
        // or
        fallbackLocale: ['en', 'fr'],
        // or
        fallbackLocale: {
            'de-CH':   ['fr', 'it'],
            'zh-Hant': ['zh-Hans'],
            'es-CL':   ['es-AR'],
            'es':      ['en-GB'],
            'pt':      ['es-AR'],
            'default': ['en', 'da']
        }
    }
}

More information in vue-i18n documentation.