Can I use i18next-browser-languageDetector before the (async) initialization of i18next

Question

I'm using i18next and i18next-browser-languageDetector like so:

await (i18next
  .use(initReactI18next)
  .use(LanguageDetector)
  .init({
    resources,

    fallbackLng: process.env.DEV ? 'dev' : DEFAULT_LANGUAGE,

    debug: Boolean(process.env.DEV),

    returnObjects: true,

    interpolation: {
      escapeValue: false,
    },

    detection: {
      // Order and from where user language should be detected:
      order: ['localStorage', 'cookie', 'navigator'],

      // Keys or params to lookup language from:
      lookupLocalStorage: I18N_LANGUAGE_KEY,
      lookupCookie: I18N_COOKIE_KEY,

      // Cache user language on:
      caches: ['localStorage', 'cookie'],

      // Only detect languages that are in the whitelist:
      checkWhitelist: true,
    },
  }));

Right now the detection is made during the initialization phase of the i18next library, which is async, so if I want to check the language that has been detected (i18next.language) I need to wait for that to finish.

The problem is I need to detect the language before i18next loads the resources in order to set the Accept-Language header in axios before any request to the backend is made.

I know I could just read localStorage, cookies or navigator myself, but I'd like to use the functionality that is already built-in in i18next-browser-languageDetector if possible.