Never used a portable freezer, or a tiny freezer before, the process would be identical to using a small apartment size refrigerator. If the space fits, why not? If you want to run the freezer off the battery, when you are towing, you could get a small inverter that hooks up to your camper battery and then you plug the refrigerator into the inverter. No need for fancy wiring, or trying to figure things out.
When you set up camp at the campsite, simply unplug from the inverter and plug the refrigerator back into 120v AC into a wall socket, or run an extension cord. it's very doable, as long as your camper has space to fit a freezer.
Something like this, click here?
Your tow vehicle will continue to trickle charge your battery when traveling. So the tow vehicle will keep the battery charged so the inverter will run. The inverter will run to keep the freezer cold. Simple, easy-peasy.