Lots of threads on geoexpat of people fleeing HK and how to get their money out. Nice to see the opposite for a change
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if you currently live in a country where you can get a revoult/wise card (HK is not one of them, wise is in HK but not the debit card, revolut is coming to HK soon), then yes sure if would be handy for you to get before you leave. This will allow you to purchase most things in HK the second you land and very good exchange rates with minimal fees.
But really you shouldn't need to do this for long, bring some cash, get an Octopus when you land for train/bus and other smaller purchases where a revlout/wise card would not work, and then it should be fairly quick for you to get your temporary HK ID, local HK bank account, then do some electronic transfers from your home country to HK if you need to bring more money across.
Once you have your local HK bank account, wise is also good for wiring money, great rates and low fees. Even better is interactive brokers, which is primarily an investment platform but also happens to give the best fx conversion rates and then allows you to depost funds from your home country bank account, withdraw to a HK bank account, but IB does have quite a complex setup and ID process.