I recently heirloomed a Deadly War Spear I had bought on the market into a Balanced War Spear. On the site it's named Tempered War Spear and for some reason it does not show up in the in game equipment list unless I choose it into the loadout on site.
I have only 2 melee weapons: the heirloomed War Spear and a Shortened Spear.
While annoying, this isn't a major bug as I can just deselect the War Spear if I don't want to use it that round. It still remains in the list of selectable items after that.