We knew that once and future Supermen (...Supermans?) would be flying in for The CW's Arrowverse crossover this fall, but fans around the world are being treated to behind-the-scenes teases of celebrities in their supersuits. It's getting hard to keep track of everyone, so for this round of crossover news, we're limiting it to a pair of Supermen: Brandon Routh and Tyler Hoechlin. The former is closing out his time on The CW's Legends of Tomorrow as Ray Palmer, a DC Comics character who got his TV start on Arrow before making the jump …