You could make a subfile with 16 and (maybe hide it in a special stickers subdir) and then import that into the real sticker file with trans-white. Then you've got an option to substitute the 16 file for the real one for better rendering if needed. The actual substitution could possibly be handled by software as an option in the renderer, or by the user if they have old software.
Having a real sticker file with trans-white could be handy for LPUB (or other) inventories.
Having a real sticker file with trans-white could be handy for LPUB (or other) inventories.