The guy in the hat is referred to as Bacchus in this tweet. I couldn't find out who he is. As for the guy to the left of Harlock, I have no clue as to who he is.
Mad TreasureOne PieceSakata GintokiGintamaHarlockUchuu Kaizoku Captain HarlockKudou Shin'ichiMeitantei ConanTotakekeDoubutsu no MoriKappaArakawa Under The BridgeArsene Lupin IIILupin IIISaburouNobunaga ConcertoHonda KouTerra FormarsSomeya TakumiRyuu Ga Gotoku 6Takiya GenjiCrowsBacchusYuusha YoshihikoHanazawa RuiHana Yori Dango