USB breakout board for turning off device - SHIELD help needed

[DanielRehak]

Hi all,
currently I design a breakout board which I plan to introduce between USB device (e.g. keyboard) and USB host (e.g. computer). For reference take a look at picture below.



On breakout board there is circuitry to enable turning VBUS off on USB device's side. That way I can turn power on/off on USB device which is crucial for my application.

I designed circuitry and tested that it works. Now I would like to add USB connectors on each side of the breakout board and interconnect everything.

I attach schematic as PDF. Please take a look at it before you comment.

I have unclear points regarding shield connection.

Please take into consideration that I do NOT have any outer metal enclosure for whole device so I cannot connect shield to it.

My questions:
1) should I interconnect 2 shields of each connector or should I leave them unconnected? Connecting them would interconnect 2 shields of 2 different USB cables.
2) should I connect shield at one side of the breakout board to GND? I want to avoid creating ground loops.