Donald Glover plays Aaron Davis, known in Marvel comics as the Prowler. When Davis mentions having a nephew in Queens, he confirms Miles Morales exists in the MCU.
Michael Mando portrays criminal Mac Gargan on the ferry. The scorpion tattoo on his neck and the prison credits scene explicitly tease his comic alter ego.
The Department of Damage Control dates back to 1989 Marvel comics. Tony Stark taking over cleanup operations directly provoked Adrian Toomes to turn into the Vulture.
Captain America's gym class PSA videos were outdated relics. His appearance reminded classmates of the Sokovia Accords fallout while Steve Rogers was officially an MCU fugitive.