The Queen mistress variant

I was looking at my Chessnut chessboard the other day and idea came to me. I thought of using the two additional queens and let them into the game even before the first pawn move. The idea is the following:

- White starts by putting their additional Queen on the 3rd rank wherever they want. 

- Black follows and also choses a position for their "mistress" queen on the 6th rank.

After this you just play à normal game of chess...

the idea is that white doesn't have the same advantage of being the first to play as they have to disclose their first move from the start and black has the option to put their queen on row 6 by looking at the best position in relation to white's choice. 

my guess is that most white players will put their "mistress" on F3 first and black will usually respond by putting their queen on e6 to defend the f7 pawn but of course may other strategies can be used.

Why "mistress"? I just imagine this additional Queen to be the one competing with the official Queen to grab the enemy king, like a sort of spy using their charms to lure the king...

A variant to this variant could be that you can decide to introduce your mistress whenever you want in the game but it has to be before you do your first move on your regular queen and it has to be on the 3rd rank (3 for white, 6 for black)