Notable episodes of the Justice League Unlimited animated series gave a nod to the Defenders by banding together a handful of DC characters with parallels to the earliest members of Marvel's non-team.
The two-part episode "The Terror Beyond" featured an unlikely alliance among Dr. Fate, Aquaman, and Solomon Grundy (acting as Dr. Strange, Sub-Mariner, and Hulk), as well as Hawkgirl. A sequel episode titled "Wake the Dead" reunited the group with the addition of the android A.M.A.Z.O. (standing in for Silver Surfer).
As a weaponed warrior with wings, Hawkgirl worked as a counterpart for both Valkyrie and Nighthawk. Solomon Grundy even referred to Hawkgirl as "Bird-Nose" (aping Hulk's nickname for Nighthawk). The irony, of course, is that Nighthawk was designed as an homage to Batman in the Squadron Sinister and later Squadron Supreme (Marvel's looking-glass version of the Justice League).
Also of interest, when the Defenders faced the Squadron Supreme (Defenders #113), Valkyrie proved evenly matched against Power Princess (the Squadron's homage to Wonder Woman). Power levels notwithstanding, Valkyrie's origin as a female warrior from Norse mythology made her similar to Wonder Woman (an Amazon tied to Roman mythology).
Hawkgirl, incidentally, did not have a direct counterpart in the Squadron Supreme, but a member of that group called Cap'n Hawk was an homage to Hawkman.