You posted in the T-Mobile forum -- are you asking specifically about smartwatches sold through T-Mobile?
I'm glad you told me. Could have sworn it had 3G. Oh this sucks.The rose gold Gear S2 Classic looks nice. I have not seen a 3G/4G cellular version of it anywhere, only bluetooth. If it were ever available with the cellular connection, I would get my wife one. It would certainly look nicer than the black.
According to this article:
https://www.lifewire.com/smartwatches-with-cellular-connectivity-4107839
"Note that the more premium-looking Gear S2 Classic is also available with 3G connectivity"