only thing tranny related on passenger side is lines,or dipstick. 99% of the time its the lines MAYBE the pan. just tighten em. If you are up north they might be rusted.
engine wise its a valve cover or oil pan. chances are valve cover.
Do it this way. pull the dipstick for the trans. Get your nose down in it and smell it. Then find the leak and wipe it and smell it. If its the same smell its the trans. if not its the engine.