Just Google Play. My game doesn't even have 1k official installs on Google play. But Unity analytics reports 36k users in China total. Admob also reports 8k+ requests from China daily.
You might want to do a Google search for your com.company.productname and see if there may be illegitimate download locations
Thanks, there are lots of edited apks of my game. Most of them have BundleId modified. But i can't find anything related to China apk stores.
Sorry, I'm not familiar with specific "China APK stores" that distribute illegal copies of your game, I doubt you will find them either. My point was that your game was likely copied and hacked, as you point out.