Yes. If the two photos are already aligned except for the second hand, put them on separate layers and use a blend mode instead of reducing opacity.

A simple choice is:

• Darken if the watch hands are darker than the dial/background
• Lighten if the hands are brighter than the dial/background

That lets Photoshop keep the darker or lighter pixels from both layers, so both second-hand positions can appear clearly at full strength.

This works best when the images are otherwise identical and only the second hand changes position. If the rest of the watch or lighting also changes, the result may affect other areas too, and you may need a mask to limit the effect to the hand.