Does it also help reduce the noise? Or is there much noise from these units?
Bunnings have a number of Wall Art panels that would have good air flow. Maybe putting some of those into a frame would make a suitable front. The sides of the one you showed is framed lattice, which would be a good set of sides to stick with. It looks simple enough, since it only needs to be strong enough to support the top piece and a few pot plants or ornaments. I'd use angle brackets inside the bottom corners to strengthen them, since there is no backpiece down there to keep it rigid. The idea looks great. Mine is hidden by a folding mesh screen that I got from Ikea. The one you are planning looks much more ornate.
Welcome to the Bunnings Workshop community @Angel1988. It's fantastic to have you join us and many thanks for your question.
You might like to read through the discussion Aircon cover / BBQ stand by @DoSimpleBetter. Within it, they show how they constructed their own cover to use as a perfect BBQ stand. As @TedBear mentioned, we have a variety of wall art panels which you could use for this build. You could consider using SpecRite 1800 x 600 x 33mm Merbau Garden Fence Panels for the sides if adequate airflow is achieved through the front.
Please let us know if you have any questions about your project.
Welcome to the Bunnings Workshop community @Angel1988.
Just wondering if you have made any progress with your project? It was great to see you receive such helpful replies. I'm sure other community members will be keen to see what you come up with as this is a common problem.