The singers of Babymetal, from left, Yui Mizuno, Suzuka Nakamoto and Moa Kikuchi, performing at the PlayStation Theater in Times Square.Credit...Justin Borucki In ponytail or pigtails, pleatherlike tops with puffy shoulders and iridescent black tulle skirts, the singers of Babymetal stood on individual six-inch risers so the crowd could see them properly. Behind them, onstage at the PlayStation Th