I think it would depend on what samsung watch you have.
About 2 years ago them the galaxy watch 4 moved to a Google operating system called wearOS.
With wear OS you can use Google pay on your watch.
However if the watch you have is watch 3 or earlier, then this used a samsung operating system known as tizenOS. This did not allow the use of Google Pay.
Samsung pay has less banks added. However if you bank isn't allowed then you can use samsung Curve to create an account. This is a kind of virtual account that allows the other banks to be added.
Hope this helps.
Smiley.
- Smiley
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