Starting off with the Black / Blue set, I will do the genderbent Hetalia characters now C:
But don't ask me to do reference sheets to them. They are too much work for me x.x
Also, this leaves room for you to make your own ideas when you make this into a cosplay.
On Fem!Germany, I left most of the outfit the same, what is different is that her chest is bind with white bands (Much like a mummy? I dunno how to describe that). It's not so well visible because of the pose.
Obviously, Germany's arms are tied together >; (I imagine this a rather uncomfortable fashion, unless you come up with a nifty trick )
King: Italy, Queen: Hungary, Rook: Germany, Knight: Austria, Bishop: Japan, Pawn: Prussia