Its hard to know exactly what to do here, without knowing which team you use, or if fantasy league your players. But I'll take a crack at it. The first thing I would do is go into Shotgun and then when the ball is snapped, maybe, drop back a little. Hopefully that will buy you some extra time. Second, put the HB to block and send him in motion, so he is close to the line when you snap. He may have a better chance to pick up a block that way. Third, if the nano blitz is coming from over the middle send the slot reciever on an inside slant and put the second back on the slot side on an outside slant, hit one of em real quick. This works in Shotgun Split back.
Also remember your default audibles, the ones on the bottom of the audible screen, one of em is a off tackle out of Shotgun split, this can be a very effective audible to mix in with passing plays.