It will shock the drivetrain, potentially causing the belt to slip and in worst case scenario, damage the gearbox.
When you shift into D while the car is coasting in N, the clutch will connect to the engine flywheel(albeit not with full pressure). If there is a big difference in the engine speed and the wheel speed, the speed difference will torque the gearbox and the engine. The gearbox, being less resilient and less weight than the engine, will bear the brunt of the torque.
In layman terms, if your drive a manual car, roll downhill at 50km/h in neutral, then suddenly masuk 1st gear and dump the clutch, your car will jerk like mad because the engine is trying to slow down the car.
Remember, the CVT gearbox is not as tough as normal MT and AT boxes. Also it is dangerous to coast downhill in neutral.
The pump will still run geh, as long as the engine is running.....but not running as fast as in D (because in D the wheels are driving the engine, hence the pump also working faster).
But you are correct that in N it will not cool as efficiently as in D.
after i read this comment, we should/can't not shift D to N when stopping for the red light? is it correct?