Striker Aguero and defender Garcia have joined Barca as they come off contract at City this month.
Alba has welcomed the pair, telling Radio Marca: “I think the arrival of Agüero and Eric Garcia is a very good thing.
"I've been told some great things about El Kun and I know Eric is good. It's good that a former member of the house is coming back."
Garcia left Barca as a 16 year-old to join City's academy.