Gus Poyet appears to have beaten off competition from Cardiff's Ole Gunnar Solskjaer to land the 28-year-old.
Scocco has been a long-term target for Sunderland, who wanted to sign him before his summer switch to Internacional.
However, the move has been complicated by the fact his current club still have to finish paying former side Newell's Old Boys for his transfer.
Earlier this month, the player's father told Radio Gaucha that two English clubs were looking to sign his son, adding: "It's not that Scocco doesn't like Brazilian football, his problem is that he didn't have motivation to keep playing for Internacional, nothing else.
"The problem is with Internacional, not with the Brazilian clubs."
Should the player join the Wearsiders, he will be the third Argentinian to head for the Stadium of Light this month with keeper Oscar Ustari and central defender Santiago Vergini already on board.
Manager Gus Poyet has also brought in Spanish full-back Marcos Alonso on loan from Fiorentina and recalled striker Connor Wickham from Sheffield Wednesday 24 hours before his loan deal was due to expire.