I don't think (re)listing on the HKEX will be a huge problem, if...

I don't think (re)listing on the HKEX will be a huge problem, if that were to happen.
A quick Google reveals quite a few options, such as:

Selfweath, based in Melbourne.
"We empower investors to make informed decisions without paying exorbitant brokerage fees."

We’re Launching Trading for HKEX Markets:
https://www.selfwealth.com.au/blog/were-launching-trading-for-hkex-markets/

Monex
"EXCLUSIVE: Trade The Hong Kong* Stock Market With ZERO Brokerage"
https://www.monexsecurities.com.au/investing-in-hong-kong-stock-market/

Phillip Capital
https://poemstrade.com.au/markets/hong-kong/

And so on.

One thing I learnt:

"Unlike the Shanghai and Shenzhen stock exchanges, Hong Kong stock exchange doesn’t have price movement restriction. But the shares of each company are traded in parcels. The number of shares in each parcel is predetermined by the company. One parcel of Tencent shares contains 100 shares and one parcel of Petro China shares contains 2,000 shares."