That’s not something that’s commonly done… Normally you want to use classes transparently, regardless of if they were implemented in blueprint or native. It might help knowing what are you trying to achieve by checking this class?
In any event, assuming UObjectChildClass is the base class you want to use for your inventory system… You already know that it is not a blueprint class since it is a native base. However, if you have an instance of such an object, you can call GetClass() on it to get the actual class of the object. For objects implemented in blueprint, GetClass() will return a special kind of class, UBlueprintGeneratedClass, which contains extra information about the blueprint data. But as mentioned, you rarely have reason to operate on those.