Loop an array asynchronously with map

loop.js

exports.getTranslations = functions.https.onRequest(async (req, res) => {
  const english_words = req.body.english_words || [];
  console.log(english_words);
  const collectionRef = admin.firestore().collection("translations");
  const createResponse = (res) => {
    var data = {
        english_word: (res === undefined) ? '' : res.english_word ,
        translation: (res === undefined) ? '' : res.translation ,
        transliteration: (res === undefined) ? '' : res.transliteration,
        sound_link: (res === undefined) ? '' : res.sound_link
    }
    return data;
  }
  const promises = english_words.map(async english_word => {
    return collectionRef.doc(english_word).get()
  })
  Promise.all(promises).then(docs => {
    translations = docs.map(x => createResponse(x.data()))
    console.log(translations)
    res.status(200).send(translations)
  }).catch(function(error) {
      console.log("Internal server error", error);
      res.status(500).send(error)
  });
});