大丈夫です

と書いておいて、
念のため確認。

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Home > Helping You Travel > Baggage > Liquids / Gels / Aerosols Restrictions
All duty free items of LAG must be accompanied with proof of purchase, and packed in a sealed tamper evident bag (Please note that some Duty Free Stores DO NOT provide sealed tamper evident bags to customers)

Hong Kong
TRANSIT: Passengers with onward connecting flights with Duty Free LAG items purchased:
Provided that items have been purchased from the HKCAD* accepted countries
Australia ありますね。