The OS compatible with Android apps is HarmonyOS (<5.0), which you can literally think of as Android + some (maybe much) Huawei stuff. The thing based on OpenHarmony is sometimes referred to as HarmonyOS Next / 5.0, and some of those having upgraded to HMOS 5.0 are always complaining its compatibility in Chinese communities. Huawei always invents so many names so that people often confuse them.