My name is Dr syed hasnain I need to ask that my wife is travelling with me to pakistan.

On return the transit time to Australia is almost 10 hrs .
She holds a Pakistani passport and have a 457 visa endorsed on it valid till 2017.
Myself and my twin boys have European union passports.
Last time my wife did not require any Transit G as she stayed at Airport before boarding a plane to Australia.
I just need to know will it still be okay for this year as well or will she be needing a transit G.
if she needs it can I apply directly to Hong kong Immigration or will I need to visit nearest chinese consulate for submitting of application form along with travel documents and other requirements.
What is the application fees for a HONG KONG visa?