Man, the Kids' WB! Days! I'm not saying it'll be exactly like that, but that hits me right in the nostalgia feels .Yeah, I don't think Caped Crusader airing alongside King of Atlantis would be that much different than Kids' WB! airing The New Batman/Superman Adventures alongside Pinky, Elmyra & the Brain or The Batman paired with Johnny Test over the years.
Also unless we're talking re-runs, King of Atlantis has only 3 episodes so it should premiere and end long before Caped Crusader comes out.