I came across a need to pass through a USB smartcard device to a VM using the VMware Horizon View client for Mac OS. My smart card reader would not show up in the list of devices to redirect to the VM. After doing some research I came across this document which outlines the commands I needed to run:

sudo defaults write com.vmware.viewusb IncludeFamily smart-card
sudo defaults write com.vmware.viewusb AllowSmartcard Enable

You can verify which settings have been applied with the following command:

sudo defaults read com.vmware.viewusb

Success! The client now sees my smartcard reader as an option to pass through to a VM guest.