Or HaChaim on Shemos 4:27

English: לך לקראת משה , "go towards Moshe, etc!" Although we have heard G'd say to Moshe already in 4,14 that his brother Aharon was on his way to meet him, the actual instruction to Aharon came from G'd while Aharon was still in Egypt. There is no question that the prophecy in this verse was adressed directly to Aharon even though we learned in Toras Kohanim 1 that wherever the Torah writes: "G'd spoke to Moshe and Aharon," that the directive was spoken to Moshe only and he in turn was to convey it to Aharon, this does not apply here. Even according to the view of Rabbi Yossi Haglili who excludes Aharon from receiving a communication from G'd directly even while both were in Egypt, he referred only to communications which concerned an independent mission to outsiders. There is no reason to believe that G'd did not speak to Aharon directly concerning what Aharon himself was to do. Our verse proves that Aharon was a prophet in his own right.