Remove the nut from the top of the sway bar link using a 17 mm socket to turn off the nut while holding the inside of the sway bar link joint with an open end 17mm wrench.

Then use the open end 17mm wrench to loosen the bottom joint of the sway bar from the hub assembly.

You'll then be able to remove the sway bar link for inspection. Save the nut and any washers as the new links do not come with replacements.