I am looking to use the sunshade I had from my 2016 Jeep Wrangler Unlimited Sport S on my new 2019 Jeep Wrangler Unlimited Sport S. Does anyone know if this will fit? The sunshade covers the front and back seats.
Probably not, though it may depend on what type you have if you can make it work. The main issue is that the JK has footman loops on the windshield frame (for either hard top or soft to connect to) that the sunshades generally attach to. The JL does not have footman loops at all. The soft top has hooks that attach to the roll bar/frame and the hard top freedom panels don't use them at all (IIRC). All the current sunshade manufacturers have gone to a clip system that attaches between the windshield and the roll bar frame. (with a couple of exceptions that are using magnets).
So to make a JK sunshade work you'll have to figure out some way to attach the front to the windshield, after that it's mostly the same though dimensions might be slighter different.