In my personal experience when the computer is connected by ethernet even to the same network it doesn’t always connect to the WiFi for debugging. I could not even have the ethernet plugged even though I am connected by WiFi. I think it has to do with the router as I know others are successful.
Try this to connect to the watch if it fails then it is because you aren’t connected by WiFi on your computer
On your watch
Enable ADB debugging
Enable WiFi debugging it will initially say not available then it will pop up a connection and have the IP address followed by .5555 (the .5555 is the port)
Using File manager copy the address where you installed adb by default
C:\Users\USERNAME\AppData\Local\Programs\WatchFaceStudio\tools\window
(copy the address as text from file manger using right click on the address bar)
Open a command prompt
navigate to the folder address
cd C:\Users\USERNAME\AppData\Local\Programs\WatchFaceStudio\tools\window
Then type
adb connect 192.168.x.x:5555 (where 192.168.x.x is your watch’s IP address).
It may take a minute to connect or give a failure response
If you get a rejected error or something check your watch debugger settings.
Try in developer options to revoked permissions and force new acceptance. do the connect again.
If you connect with that you should be all set to go from WFS run on device. If you can’t install it may be that your keystore.jks file isn’t right.
In the US you can buy a USB WiFi receiver for less than $20 You might have to use that. Again you might have to unplug the ethernet.
Hope this helps.
Ron
Samsung Developer Relations
I think the Samsung Galaxy watches block Bluetooth debugging. As the instructions for bluetooth debugging won’t work on Samsung watches.