hello
I have problem with hdd , how it is formatted , HIMEDIA usb3.0(slave) does not work? 
I would recommend you read this thread carefully and try again (thanks to @OlivierQC):
http://www.futeko.com/newforum/index.php?topic=932.0
If you still have issues you need to be very specific about the HDD, if pre-formatted, what system you are connecting to and what techniques you have tried and what is happening on your system.
I found the USB 3.0 plug at the rear makes the Q10 Pro work fine as a slave (external drive) when plugged into a Windows 10 PC.
A "does not work" is not enough information for anyone to be able to help you.
If you wanted to plug an external hard drive into the Q10 Pro you would use one of the side USB ports (of course).