Turner is a wing SG/SF who is an ineffective scorer but a multi-dimensional role player. An above average rebounder, ball-handler and passer at both wing spots. An above average defender at the SG position but only a middle of the pack one at SF (below average vs starting SF).
Jeff Green is a combo forward SF/PF who is a scorer/defender. A 3rd/4th option offensively. A strong defensive player whose combination of size, strength, quickness and length allows him to matchup physically against top athletes at SF position (which E.Turner cannot do at SF). A below par rebounder and mediocre passer and ball-handler.
Jeff Green has some negative value as rebounder and adds little value to his team outside scoring/defending ... in contrast to Turner who adds negative value with scoring but really good value via rebounding, ball-handling, passing and defending (when SG, less so at SF).