Black Cats boss Peter Reid has been tracking the 21-year-old, as he looks to boost squad of strugglers ahead of next season.
De Muner is a former Argentine Under-20 international and should he make the switch to the Stadium of Light, he would be the third Argentinos Juniors player to arrive on Wearside, after Julio Arca and Nicolas Medina both made similar moves to the Premiership outfit.
He played with Arca and Medina in the South American Under-20 Championships last year but was overlooked by Under-20 boss Jose Pekerman for his country's successful hosting of last summer's World Youth Championships.
A move for de Muner could add to Reid's defensive options next season, as Sunderland look to halt the slide that has seen them drop to fourth from bottom in the Premiership table with two matches remaining.
