Found this:

Javier Milei, Argentina’s president-elect, is noted to have participated in events organized by the World Economic Forum (WEF) in the past, such as a 2014 forum on Latin America. His participation has led some to associate him with the WEF, though he is not a known member of the organization itself. Milei is publicly critical of globalist institutions and uses platforms like WEF conferences to advocate for his ultraliberal, free-market policies, which he believes are contrary to the WEF's globalist agenda

Thus, while he has interacted with the WEF on certain occasions, he aligns himself ideologically against its central principles.

So he is rather anti WEF what I understand