I put in a ticket on this. Presonus' response was:
Thank you for contacting PreSonus!
Unfortunately, channel naming is not supported for the USB version of the StudioLive 16.0.2 USB.
This feature was available for the Firewire consoles by setting the "Other" permission to "Ch Rename" in the older Universal Control.
This is not supported in the newer/USB version.
Please give the USB Studio Live 16.0.2 mixers this capability like that of the legacy firewire models.