Okay, so yes, take this with a pinch of salt. Feel free to follow my logic – and reject any and all conclusions I draw. I am showing all my working out and it's up to you whether or not you follow my thread.
Loki is a new TV series currently being made, starring Tom Hiddleston, reprising his role from Thor and Avengers, and to air on Disney +. Well, Bleeding Cool gets the word that the production team for the show has been ordering all manner of material, with the common thread being the appearance of the Squadron Supreme.
The original team was created in the late sixties/early seventies by Roy Thomas and John Buscema, and derived from their previously created parallel dimension supervillain team Squadron Sinister, containing Hyperion, Nighthawk, Doctor Spectrum, Power Princess, and the Whizzer. Members of both teams were based on Justice League characters published by rival DC Comics.
The team then had guest appearances on several more occasions, and in 1985 was featured in a critically acclaimed twelve-issue limited series by Mark Gruenwald.
A more recent iteration of team, set in Marvel's mainstream 616 reality, features characters from numerous alternate universes, such as the Nighthawk from Supreme Power, a Hyperion from a reality that had been destroyed upon colliding with another universe, Doctor Spectrum from the world of the Great Society, Blur from the New Universe, and Warrior Woman from a Secret Wars tie-in, posing as Power Princess.
While in the Avengers titles, the Squadron Supreme of America have been created by Thunderbolt Ross and Phil Coulson, as a national alternative to the international Avengers, with Hyperion, Power Princess, Nighthawk, Blur, and Doctor Spectrum as their leader.
What version, if any, we will get in Loki, we don't yet know. But first appearances of the Squadron Sinister (Avengers #69/70, 1969) and Squadron Supreme (Avengers #85, 1970)may be or note to modern day speculators, as well as their own series over the years.