Random encounter. No prep time. Both heroes stand in each others way on a mission they are both desperate to complete and will use any means necessary to succeed.
Tech: All tech and weapons available in their respective movies/shows. Morals on/In character.
Location: Atlanta, GA. Midday.
Starting position: On building rooftops 100ft apart on opposite sides.
Director Coulson and his team need help to take down an unexpected threat: The New S.H.I.E.L.D. An offshoot of S.H.I.E.L.D spawning from the wreckage that Director Fury left has risen to do away with S.H.I.E.L.D's old practices. They don't believe in Coulson's way of running S.H.I.E.L.D and the secrets he keeps. He's just a worse version of Nick Fury to them doomed for destruction.
99% of Coulsons team was captured by the New S.H.I.E.L.D with Coulson narrowly escaping. He gives his old associate Hawkeye a call. The plan is to infiltrate New S.H.I.E.L.D's base and take out everyone there to recapture their headquarters and crew. New S.H.I.E.L.D knows the connections that Coulson has and prepares themselves by contacting a famous vigilante who would agree with their ideals: The Green Arrow.
Both hero's are unaware who the other is or what they are capable of.
Arrow is standing guard on the rooftops, unaware what opposition he may face. Hawkeye is also navigating the rooftops, headed straight towards Arrow's location, also unaware who he is encountering. Hawkeye just gets over the top of a building to see Oliver Queen keeping watch, 100 feet away, staring directly at him. Oliver, seeing an intruder, takes aim and calls out: "Who are you and why are you here?" Hawkeye now knows this is his enemy. He puts his hands up but manages to let off a smoke grenade while taking cover behind a obstruction on the rooftop.