We have no idea what language was spoken by Adam and Eve. We know that in the Millennium of the Kingdom of God, the world will speak a "pure" language.
Zephaniah 3:9 For then will I turn to the people a pure language, that they may all call upon the name of the LORD, to serve him with one consent.
It may well be that then we will speak the language spoken by our first parents before they sinned.
I hope you have found this helpful.