Backing up smartphones is already commonplace. In many cases, such a solution allows, among other things, to quickly transfer data to new equipment and protects the user against data loss in the event of hardware failure. Google is probably working on creating a similar solution for its smartwatches using Wear OS.
In the source code of the new beta version of Google Play Services marked with the number 22.32.12, a note was found to create a backup for watches using Wear OS. In this case, the data could be transferred to the watch if you buy a new phone. At the moment, this is not possible and if you change your phone, you must delete the data from the watch before connecting it to the new device.