The Black Cats were initially interested in Scocco during the summer, but the Argentine international instead chose to join Internacional having also received offers from a number of other clubs.
The Brazilian side are still thought to be paying off Scocco's former club Newell's Old Boys for the transfer, which is complicating any potential move to the Stadium of Light.
Cardiff City were rumoured to have joined Sunderland in the race to sign the 28-year-old, but it is the club from Wearside who have moved into pole position, according to PA.
Sunderland manager Gus Poyet has already brought in two Argentinians this month, with Oscar Ustari and Santiago Vergini both joining the club, while he has also signed Marcos Alonso on loan and recalled Connor Wickham from Sheffield Wednesday.
The Black Cats currently sit 19th in the Premier League table, one point from safety.