I never knew Romanian was part of the Romance language family. It's interesting to see comparisons here to many other Western European languages (Italian, French, Spanish, Portuguese) but also see similarities to Slavic languages. Unless I'm wrong, I imagine esti (sorry I can't do accents now) is similar to "jestes" in Polish?
Seems to be quite common in Romanian that you pronounce some words that begins with an E with the Y-sound before. El = yel. Ea = ya. Ei = yey. Eu = yeu.
Edit: I did some research and the words themselves are of latin origin but the pronunciations of the j/y sounds were of slavic influence.
I don't know as is usually in the live daily, but second personal formal and informal is true:
Formal Dumneavoastră sunteți (ru)= usted es (Spnish), você é (portuguese), Lei é (Italian), vous est (french) = you are
Informal Tu esti (ru)= Tú eres (Spnish), tu és (portuguese), tu sei (Italian), tu es (french) = you are