This look is typically created in post-processing by adding blue to the shadows while keeping highlights less blue, then boosting overall color intensity.

A common way is to edit the blue channel with Curves or Levels:

• Raise the shadow end of the blue channel to make dark tones bluer.
• Slightly lower the highlight end if needed so bright areas don’t go overly blue.
• Increase saturation if the image needs more vivid color overall.

In Photoshop, Selective Color can also help. One community method was:

• Add a Selective Color adjustment layer.
• Choose Blacks.
• Reduce Yellows slightly and increase Black to deepen the cool, dramatic look.

If you’re working from RAW, adjusting white balance/color temperature cooler during processing can also move the image toward this style.

If you only have a JPEG, a rough alternative is adding a blue-filled layer and blending it with reduced opacity for a subtle cool cast.

For the best result, start with an image that already has strong colors and good contrast, then apply the blue-toned grading carefully so skin tones and highlights still look natural.