Apple wireless charge can charge the watch, because for Apple wireless charge, Apple wireless charge is a standard charging protocol charger, Apple wireless charge can charge any wireless charging device, and for the watch, as long as the watch supports wireless charging, you can use Apple wireless charge to charge, so Apple wireless charge can charge the watch
The iwatch cannot be charged directly with the iphone's wireless charger. Since the battery capacity of the iWatch is relatively small and the power consumption of the iWatch itself is not very high, the charging power of the iWatch is far lower than that of the iPhone, so the wireless charger of the iPhone gives the iWatch too much power.
Apple Wireless Charging is available from individual models of Apple Watch and only supports watches that support wireless charging.