Apple Watch owners having firmware problems can now try recovering their wearable device directly from an iPhone. This wireless method, while not foolproof, can avoid a trip to Apple for service. If your Apple Watch freezes up, crashes during the update process, or stops working, it may prompt you to initiate a restore. To use this feature, the iPhone requires iOS 15.4 or later and the Apple Watch must be running watchOS 8.5 or later.
According to Apple Support: