Adjustment Brush & Color Range Mask: Can Eyedropper be Used to Deselect a Color?

When processing bird in flight photos, I'll often setup an adjustment brush with a small amount of noise reduction, paint the entire photo and then use the range mask eyedropper tool to select just the blue sky so the noise reduction is applied only to the background. Is it possible to use the eyedropper tool in combination with a keyboard key (Windows 10 Home laptop) to click on the blue sky and remove that as the area affected by the adjustment brush? I've tried pressing Alt+Click with eyedropper; Fn+click with eyedropper and Ctl+click with eyedropper. None produces the desired effect of deselecting areas of a specific color...in this case, a blue sky.

Before suggesting to the devs that this functionality be added, I wanted to ask the community if it's already there and I'm just missing the keystroke combination which activates it. Thanks in advance for any clarification you many may be able to offer.