Fight takes place in Savage Land. Green Arrow somehow is in the Savage Land now lost and suddenly later runs into Stegron. Starting the fight who wins.
Actually I wouldn't be so sure. Green Arrow could pull out a win. If Green Arrow uses his Sticky Arrow to get Stegron stuck. He could then use his cryonic arrow to freeze him. (Stegron is vulnerable to drops in temperature because of his reptilian nature). Plus that would go for Lizard as well. If he did fight him.
they are both far past human level reaction time/reflexes......and they both possess the power to easily kill him with one shot.........and it's not like CIS even comes into play, seeing as they both have no affinity towards human kind