i18next
  .init({
    resources: {
      en: {
        translations: {
          "one": "one",
          "one_dollar": "$$t(one)"
        },
      },
      fr: {
        translations: {
          "one": "un"
        },
      },
    },
    supportedLngs: ["en", "fr"],
    fallbackNS: "translations",
    defaultNS: "translations",
    fallbackLng: "en",
    defaultLng: "en",
  })
  .then((t) => {
    console.log('en: '   t("one_dollar", { lng: 'en' })); // en: $one
    console.log('fr: '   t("one_dollar", { lng: 'fr' })); // fr: $un
  });

i18next
  .init({
    resources: {
      en: {
        translations: {
          "one": "one",
          "one_dollar": "$$t(one)",
          "two": "two",
          "two_dollars": "$$t(two)"
        },
      },
      fr: {
        translations: {
          "one": "un",
          "two": "deux",
          "two_dollars": "$$t(two)"
        },
      },
    },
    supportedLngs: ["en", "fr"],
    fallbackNS: "translations",
    defaultNS: "translations",
    fallbackLng: "en",
    defaultLng: "en",
  })
  .then((t) => {
    console.log("en: "   t("one_dollar")); // en: $one
    console.log("en: "   t("two_dollars")); // en: $two
    i18next.changeLanguage("fr");
    console.log("fr: "   t("one_dollar")); // fr: $one
    console.log("fr: "   t("two_dollars")); // fr: $deux
  });