Warning: The following feature contains SPOILERS for Stargirl season 1, episode 9, "Brainwave."
DC Universe's Stargirl season 1, episode 9 confirmed that Green Arrow exists in the new Arrowverse's Earth-2. While he isn't referred to by his codename or as Oliver Queen, a photo from Pat Dugan's past clearly depicts a figure clad in the original Green Arrow costume from the Golden Age of American Comics, as well as his sidekick, Speedy.
Green Arrow first appeared in More Fun Comics #73 in November 1941, but several issues would pass before he would be given a formal origin story in More Fun Comics #89. Originally Oliver Queen was closer to Indiana Jones than Robinson Crusoe, being an archaeologist and anthropologist whose area of expertise was Native American cultures. An avid archer and hunter trained in the same techniques used by the peoples he studied, Queen was waylaid by tomb raiders while on an archaeological dig in a remote region known as the Lost Mesa. Teaming with Roy Harper, a boy whose family had been killed during a plane crash that left him stranded on the Lost Mesa, Queen was able to defeat the criminals. Queen later adopted Harper and the two decided to keep fighting crime together as Green Arrow and Speedy. It would be almost two decades before Jack Kirby gave Green Arrow a new background that involved his developing his Olympian-level archery skills while shipwrecked.
Stargirl season 1, episode 9, "Brainwave," revealed the existence of Green Arrow through a photo that Pat Dugan showed Courtney Whitmore, while he was telling her about his adventures as Stripsey alongside Sylvester Pemberton, the Star-Spangled Kid. Pat explained that he and Pemberton were part of another superhero team before they became involved with the Justice Society of America and Pemberton became Starman; The Seven Soldiers of Victory. The black-and-white photo showed Dugan and Pemberton with six other costumed figures, including a man and a boy dressed in the original costumes of Green Arrow and Speedy.
Courtney was less than impressed, asking why they were called the Seven Soldiers when there were eight of them and mockingly noting that the team had "Robin Hood and a knight" along with "a cowboy, like The Village People." Pat was quick to defend his former teammates, identifying the cowboy as the Vigilante, along with the Crimson Avenger and his sidekick, Wing. Pat did not mention the names of Green Arrow, Speedy, or the Shining Knight, but he said they were all "good men trying their best" despite the team never getting the recognition that the Justice Society of America did.
Pat noted that he lost track of the other Seven Soldiers over the years, but he wished he had kept in touch with them since the new JSA needed all the help they could get against the Injustice Society. Thankfully, it seems that the Shining Knight is already close at hand, based on the earlier episodes of Stargirl. This suggests it is entirely possible that Green Arrow might make an appearance as well, though it probably won't be Stephen Amell in a cameo appearance.
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