Find a good image to use as your App icon, preferably a .png icon.

I used this image here as my icon, you can use it if you want.

Now, open Image2Icon and drag and drop the image you want as the icon into the Image2Icon window.

Drag the Connect to AirPods Application into the Image2Icon window

You should see your Application with the icon you selected with now. You may need to right click it and open it thru there because it probably will say it is from an unidentified developer and block it. You will need to be an admin to bypass this too.