The latest episode of Heroic Insider has included a comment suggest whom they've heard as a potential directing candidate for the 2020 release: "George Miller is being rumored to direct the Green Lantern Corps movie. I think it would be perfect for him."
As many as three human Green Lanterns are rumored to feature in the new film. Miller already has a hand in the Dceu as a producer on the currently in production "Justice League: Part One".
In related news, screenwriter Mark Lamprell has spoken about an old project of Miller's - a film adaptation of Carl Sagan's "Contact". Filmmaker Robert Zemeckis was the one who directed the well-regarded 1997 film adaptation,