When your stopped at a light with the car in gear. The dashboard rattles. If you put the car
In park the noise stops, is it because there is more vibration when the car is
In drive?? Dashboard is plastic

Check for worn motor mounts.
While the trans is in gear, the idle will be slightly lower and the noise is more easily transmitted into the rest of the vehicle.
Generally speaking, how smooth is the engine idle, despite the dash vibration?