Sosa's agent reportedly flew to England this past week to conclude negotiations over a £13.5m deal and assist with the application for authorisation for the midfielder to play in England.
Gol de Vestuario tweeted earlier today, however, that Sosa has not been granted a permit and Olé suggest the move is on the brink of "collapse". This expected development could force Everton to loan him out initially like they have done with Henry Onyekuru until he has accrued enough international caps to qualify.
Sosa has still only appeared to Argentina's U20s but Marcel Brands has been sufficiently impressed with him to trigger his release clause to bring him to Europe.
Sosa's father appeared to suggest last week that his son was due to receive a European Union passport by the end of the year and, depending on Brexit, that could be the way for him to play in the Premier League.
Update Sosa's application for an EU passport remains in the balance and it appears as though Everton can appeal the decision by the Premier League to deny his work permit in the week of 17 June.