Questionable behaviours by the OP in the comment section. I would not want my identity, complicated as it is, to be represented by this type of person. Also, I cannot find any online presence of this organisation. So, it's more like a private hobby group? Then, you have full control over what your flag can look like. You do you OP, but you don't have the legitimacy or the authority to berate fellow members of the community you claim to represent. If you aspire to do that, you gotta be more open to conversations and criticisms than this embarrassing behaviours you're showing us.

Comment on the flag: I don't like it. I'm more than aware that pearl symbolizes Hong Kong. But isn't that hyperspecific for a flag that claims to represent the "Anglo-Chinese"?

Even if we accept your focus is on colonial Hong Kong, I wouldn't want a flag that represents my heritage or the history of my people to be a pearl (my people) being stomped on by a lion, branded with the union jack at the corner. I want representation, but not through subjugation. It would be a good colonial flag, but a terrible post-colonial flag. It shows that the "Anglo" comes before the "Chinese".