Already been done, PeterT. Synth accordions have been around for
at least two decades now.

Latest versions are MIDI instruments.

There's even a MIDI melodeon which is catching on, called
the 'Streb'

At the same time, there is still something to be said for
all that vibrating metal and rushing air. Even with all the
synth piano accordions, when you see an accordion in a rock-and-roll
band, it's just about always an 'organic' one.