Matchmaking on PS4 is currently broken as of launch, however developers have acknowledged this and should be issuing a patch in the coming week(s). Until then, here's what Harada himself suggested.
Head to Ranked match, Match list (recommend to set these options to any), choose your character. A dialog box will show up and tell you its searching for a game session. If a game pops up on the list, ignore it, otherwise after waiting some text at the bottom of the list will show "searching for game session". Wait for this, and it will find you a game, confirm it and proceed to play your opponent. Win, and the trophy will be yours.