There is no problem doing what you say however, I doubt the term downshifting applies (downshifting means going into a lower gear and utilizing the higher compression to slow your bike or it can also be a means to quickly raise rpms prior to getting on the throttle if you require a burst of acceleration). See ya….Gary aka wtf
You can downshift while stopped as long as you have the clutch engaged. However, the Motorcycle Safety Foundation teaches that you should downshift as you are braking so you can quickly get out of the way if the car behind you hasn’t noticed that you stopped.