Here are the edited models of the Pavise crossbowmen, Pavise crossbowmen militia, and Genoese crossbowmen that will allow the unit to use their shields in melee (Genoese crossbowmen militia, Mercenary Pavise crossbowmen use Genoese models in the stock game, while the Livonian Auxiliary unit from the Teutonic campaign uses the Pavise crossbowmen models). I am assuming everyone downloading the files will know how to install them.
Enjoy!
Contents of the original discussion in spoiler for those who are curious as to how it was done.