No.
You must check the instruments after engine start for every flight. Even if you do not push back. It is the same procedure in Cessna. In PMDG the "compass" instruments are already powered even before engine start. In that airplane they are checked before the doors are closed. But in all airplanes the compasses are checked and set at some point on the ground, before the aircraft moves for the runway. Even if their systems are different.
The last place to check the Compass, DRMI, Heading Indicators is on the takeoff runway in takeoff position. This last check has 2 purposes.
1. Last chance to find instrument failure/error before takeoff.
2. Make sure all instruments and crew agree you have chosen the correct runway for takeoff.
Flight simulator has shown how you can kill an entire airplane of people with mistake 1 ("Connie lost in space"). Many real people have died because of mistake 2.