played against two opponents playing this formation. One was inferior one was superior than me. I won both... I played 3N-4-2-1
as shown below
1ST
1AMC 1AMC
1ML-1MC - 1MC-1MR

1DC-1DC-1DC

seeing that his left DC is weaker I would suggest you use your ST on the right position, on that DC. Passing should be mixed with hort passes. Hard attacking and RED arrows on your AMC's. Play arround with full pitch or own half defence. It depends on what he is playing.