You don’t need that. Just change the ATF frequently (every 30-40k miles) to extend the CVT lifetime. 

I think you'd be wasting your money. Staying on top of fluid changes is a much better way to make sure you get the most life possible out of it.

Unless you’re using it outside it’s intended scope of usage, I’d listen to @yaser

Your transmission is designed to run optimally at a certain temperature with a certain amount of fluid. Transmission fluid expands and contracts quite a bit in relation to the temperature. You would not want to run your transmission below (or above) that optimal temperature for extended periods of time. 

Sometimes down South when we have 100 degree weather, a cooler with a thermostatic fan doesn’t seem like a bad idea. if you were using your Camry to Pull a trailer, it might also be advisable. Or If you are constantly carpooling a bunch of fat people like me to weight watcher meeting...

I just purchased a Toyota matrix with 190,000 miles. previous owners took it to the dealer, who inspected the transmission but never replaced the fluid. that’s a head scratcher. That’s the first thing I did when I got it home. Now I notice some slight noise from the transmission that indicates a certain amount of friction. I’m going to remove a little of the fluid and put some Lucas treatment in it. and, yes, I’m going to install a transmission cooler. Because what the hay?