The Casimir effect is an electromagentic effect:
The typical example is of the two uncharged conductive plates in a vacuum, placed a few nanometers apart. In a classical description, the lack of an external field means that there is no field between the plates, and no force would be measured between them.1 When this field is instead studied using the quantum electrodynamic vacuum, it is seen that the plates do affect the virtual photons which constitute the field, and generate a net force2 – either an attraction or a repulsion depending on the specific arrangement of the two plates.
Bold mine.
In this paper the Casimir force has to be taken into account for vibrating plates, seems it can impede electromagnetic transmission of vibrations, so it is possible vibrations in one plate may be transformed electromagnetically to the other plate , as the Casimir effect is seen as a force.
The vibrating plates, if a setup is made, in a vacuum will not transfer sound anyway, as vacuum has no medium.If the outside of the plates is in air only very small distances of sound transmission can be utilized.
I do not see why in order to transfer sound in space you have to do it with the complicated Casimir effect. Satellites transfer sound with radio waves all the time, to earth and to other satellites. Electromagnetic waves work best in vacuum after all.