Im wondering what color soft plastics you guys would tie on if you where fishing a stained green river?

I would stay with the natural colors. Watermelon, Watermelon seed, pumpkinseed. Those colrs should work for you.

I second that.

flukes or bait fish type soft plastic go with the natural colors that also that resemble bait fish. Would you eat a purple hamburger? I might and bass will but these are safe colors to start with. from there you might try some crazier colors. Bubblegum  and cotton candy come to mind. Dark colors are also safe, Black , Purple, motor oil, and junebug are good darks.

I wouldn't say natural, but I'd say dark. Purple, blue and black are probably your best bets.