You are polishing the paint layers so the plastic panels need no extra care other than the usual care you take when using machine polishers. Also a DA is a safer option in itself.
If you're using a clay bar - i'd recommend getting the paint layer thickness measured, especially if you're machine polishing and sealing afterwards - the panels are uneven in their thickness and you increase the chance of strike through if you use an aggresive polish.
Take your time, mask up the plastic trims and window seals etc, do a panel at a time and you'll be amazed at the results though.
You’re pretty safe with a DA, you won’t burn through on the panels, just take care on the edges as you would on any of the other panels. The clearcoat on renaults is pretty tough, I’ve used a rotary on my Clios and never has a problem. Certainly using clay won’t do any damage at all. Keep the clay in a bucket of warm soapy water and use quick detailer or similar to keep the panels lubed