Are the shoes with a nike day on the heel genuine?

Yes,

The shoes are mainly blue in tone, and the upper materials include mesh, pig leather and canvas, creating a progression of colors from light to dark. Changes, with white full-length visible air cushion, midsole and Swoosh Logo. The most distinctive "Have a Nike Day" slogan is used as a shoe theme in the form of "cross-labeling" throughout the iconic streamlined design of Air Max 97, with a black smiley face label added to the upper.