While I personally believe it's a waste of luggage space, electricity and being overly "frugal", it is something that a number of cruisers have done. I've heard the whir of a blender on a couple of cruises. The one I remember was from our neighbors on Celebrity, Mercury. They were in a Sky Suite.
I don't know if the new baggage scanning procedures would flag a blender or not. I think I'd just go for it on the rocks and buy the blended drinks.
It's a cruise not a camping trip.
Take care,
Mike