In National museum, they use lyophilisation mainly for preservation of mushrooms, with excelent results. Director tried it on some amphibians but he was not content with it. Using this method for inverts is interesting idea.
Lyophilization could possibly leave some specimens looking faded or translucent like freeze dried food. Of course freeze dried food retains its original color when it is re-hydrated. It would be interesting to see if a lyophilized invert could be re-hydrated using a chemical like glycerin or linseed oil to make it less brittle, stronger and or protect the shell and prevent fading.