Ethnic Chinese participation rates are very high in women's cricket, literally 50% of them are Chinese and some of the Nat team's best players are Chinese. This is because Cricket HK has put a lot of investment into developing grassroots cricket in HK, and since women's cricket in HK is relatively new and still growing, there is plenty of scope for the the local Chinese to be involved.
However Men's cricket tends to be dominated by the expats. Cricket HK was basically set up by the expat cricket community. There was no real local cricket community here to begin with,
the sport came over when the British moved here, and was exclusively the domain for non-chinese for quite a while. Since then, from what I've observed so far, most of the participation at grassroot levels naturally comes from the sons of these expats. They play it in the streets and grow up watching it. So most of the talent, even at youth level, is non-Chinese. And at domestic levels you ofcourse have all these immigrants who have learned the game overseas, but who now live in HK.
But there is still all the grassroots investment happening by CHK. We also have two full-Chinese teams in the Saturday league (35 over stuff) and one full-Chinese team in the Sunday league (50 overs stuff), and they're starting to become quite competitive. There have also been five ethnic Chinese signed to the recent T20 Blitz, and quite a few of the best players have gone on tours with the Nat side. One even had a developmental deal with a Big Bash team (Sydney Sixers IIRC).
All the promotional activities done by CHK are done in Cantonese as well as English, with a clear emphasis on attracting the local Chinese to the game. I have played, coached, and even attended umpiring training alongside a lot of local Chinese. They are definitely involved in HK cricket, and their participation is growing with time
A Pakistani coach/former top-level domestic player in HK was telling me how recently there was a 'Introduction to Cricket' workshop being held, and in it he saw something he never thought he'd see from the day he started playing cricket in HK - two chinese women teaching two white men how to play cricket. I think that sums up how far CHK has come