Most listed companies in Hong Kong take BVI as their shareholders. Because BVI has strict protection for shareholders, and buying and selling shares of BVI company is tax-free, most listed companies in Hong Kong use BVI as their shareholding platform. The simplest example, China Mobile's listing in Hongkong is to use BVI company to hold shares. Most red-chip listed companies will use BVI as their shareholding platform.
As for mainland listed companies, in principle, they can directly use BVI to hold shares, but in practice, Hong Kong companies or Singapore companies are rarely used, that is, BVI holds shares in Hong Kong companies and Hong Kong companies invest in mainland companies. This is mainly due to income tax considerations. Dividend income of Hong Kong companies can be taxed at 5%, but BVI cannot.