Well, yes AND no.
A benchtop belt and disc sander is one of the most handy tools in my shop. You can use it to flatten handle scales, minor grinding, and some major handle shaping.
Most will use a bigger belt sander(grinder) to shape blades and work progressively to finer grits, until all that is needed is minor buffing from a buffer to polish it.
I have hand sanded blades entirely by hand, wet sanding, and hand polishing to a mirror finish.
Some of the better knife makers here prefer a satin finish on the blade, finished by hand.
All that said, if you have permission, get the benchtop belt/disc sander, you won't regret it and it is handy for other projects other than knives too.
Dan