For anyone who finds this in the future, ironman accounts can use their shield half on another player, or have a shield half used on them, to "trade" them.
This can be done with the candlestick for Hero's Quest too.
('m not sure about the key part for Black Arm's, I went Phoenix on my iron)
I mean if you read what i wrote you can see that i said that the shield is tradable with right click use, and that the key isn't . And yh as for now you need mod help if you chose black arm gang on ironman and I knew that from months ago , but i thought they made the key tradable by now . I hope this is gonna get fixed sometimes soon for future ironmans.