Can Australian students travel from Sydney to Hong Kong with China passports?

Australian students can travel from Sydney to Hongkong with China passports.

① An Australian passport can stay in Hong Kong for 90 days without a visa, whether you leave from Chinese mainland or enter Hong Kong from Australia or other countries or regions.

② If you pass through Hong Kong with a China passport and a valid Chinese mainland visa, you can stay in Hong Kong for seven days without an entry permit. If you don't complete your trip to a third country via Hong Kong, you will be noticed by the Hong Kong Immigration Department. If this trick is used too much, it will be blacklisted.

(3) You can apply for a visit visa for more than two years, but you can only stay in China for 90 days at a time, and you have to go to Hongkong or Macau.