would take a tremendous codding effort which even me, with my love for customization would not approve, since you have to make these feature with a Rule to turn them on and off, since not everyone will agree exactly which weapon should have bonus vs which body type. As a GM of table top DnD style games, I some times have ocasions when game stops for HOURS with everyone trying ot prove their point why a Sword can or cannot damage a Clay Golem
if you want a more simple work around- why don't you use BANE dmg bonus?
ok given bane can only be assigned vs 1 race and 1 body on any given item, but its better than nothing.
I am also curious if bane could be made negative...