The Wear OS screenshot must not show any clocks. Just the screenshot. Without anything around it.
One screenshot is sufficient for Wear OS.
Use the screenshot from the Watch Face Studio workspace and convert it 1: 1 into a jpeg without a background.
Here I have explained the entire procedure again.
https://forum.developer.samsung.com/t/step-by-step-with-images-to-upload-a-face-in-play-console/17282/2