In 2020, Hahn starred in the HBO drama miniseries "I Know This Much Is True", based on the novel of the same name by Wally Lamb opposite Mark Ruffalo. That same year, Hahn began voicing Paige Hunter in the Apple TV+ animated musical comedy series "Central Park". Apple Inc. had given a two-season order to "Central Park", with each season set to consist of thirteen episodes. In 2021, Hahn joined the Marvel Cinematic Universe by starring in the Disney+ limited series "WandaVision" as Agnes, a mysterious "nosy neighbor", later revealed to be Agatha Harkness. She will next star in the Apple TV+ miniseries "The Shrink Next Door".