God made him who had no sin to be sin for us, so that in him we might become the righteousness of God. (NIV)

For our sake He made Christ [virtually] to be sin Who knew no sin, so that in and through Him we might become [endued with, viewed as being in, and examples of] the righteousness of God [what we ought to be, approved and acceptable and in right relationship with Him, by His goodness]. (AMP)

For he hath made him to be sin for us, who knew no sin; that we might be made the righteousness of God in him. (KJV)