After teasing and making multiple easter eggs to Green Lantern in the show, including Barry going to Ferris Aircraft, Coast City, and mentioning a missing test pilot that worked for Ferris Air, fans have been wondering if Hal Jordan/Green Lantern would make an apperance in the second season of The Flash or (Green) Arrow. In an earlier interveiw Arrow showrunner Marc Guggenheim (the king of Olicity) had said that is unlikely for Hal Jordan to appear in Arrow due to the Green Lantern Corps movie being released in five years, even though Arrow's flashbacks in season four take place in Coast City ! Now, in response to a fan, Grant Gustin seems to have confirmed on his twitter account that Green Lantern will not appear on his show either.
Green Lantern is not the first character that the DCTV Universe has been cut off from using. Arrow was forced to replace Ted Kord (The Blue Beetle) with Ray Palmer (The Atom) last season, and also had erase all Harley Quinn plans and kill off Deadshot due the Suicide Squad movie coming out next year. The Flash was forced to cut out a Lex Luthor easter egg due to Batman Vs Superman: Dawn of Justice and neither show can even mention Gotham or Metropolis, which is weird becuase Supergirl and Gotham mention them all the time, and The Flash made a Batman reference in it's first episode. Even Legends Of Tomorrow has also been stopped from using Booster Gold, even though his son, Rip Hunter, is one of the show's main characters.
On the bright side their is no lack of heroes coming to DCTV, even with these restrictions. Jay Garrick, Wally West/Kid Flash, Dr. Light, Atom-Smasher, Hawkman, and Hawkgirl are all set to appear in the next season of The Flash. Along with Mr. Terrific and Constantine appearing on the next season of Arrow, and Red Tornado set to make an apperance in Supergirl.