Trading of Pre-order

I have seen people offering to trade pre-order items.
I myself would like a Chimeric Prism rather than my shield.

How is this possible?

I realize the pre-order item is linked to the pre-order key.

Aren't we going to receive a second key with our actual game?

At that point enter in the special key from that dealer for the item?

I'm not getting my game until tonight or possibly tomorrow.

It just seems there are a few European players wanting a bow, shield or other item they don't have access to.

It'd be nice to help each other out...

Mind