What are the minimum conditions for Hong Kong citizens to emigrate overseas?

That depends on which country you go to. I remember that Canada, New Zealand and Australia, where I applied, all had to take foreign language exams. Of course, the more education/skills, the better. It also depends on who they want locally. As for how much assets they want, immigrants are divided into two categories: skilled immigrants and investment immigrants. Skilled immigrants generally have no asset requirements, but investment immigrants definitely need a lot. It's much easier if you have relatives who are local citizens. Why not ask at the consulate?