Loki head writer touches on a reference to Agent Coulson from the show's first episode.
Loki Writer Addresses Phil Coulson's Agents of SHIELD Resurrection
Phil Coulson's Resurrection Turned His Avengers Tragedy Into Pure Horror
Disney+, Page 125 of 155
Agents of SHIELD Declares Loki In Avengers Is Coulson's Best Death
Michael Waldron, Page 2 of 2
The Direct
Disney+, Page 126 of 156
Phil Coulson, Marvel Cinematic Universe Wiki
Michael Waldron, Page 2 of 2