This is the idea but use an art canvas with depth and place the hinge on the right hand side.

What is the little box to the right and down? Usually the easy answer is a piece of art on a hinge as shown but that bit on the right is an issue for sure and when you choose the art IMO it needs to be as lage as the space so that it looks centered on the wall. Reread and you will need to move the light switch which can be done by a n electrician quite easily usually.

My mother hung a tapestry over hers. Specifically, this one, to give you an idea. It is a print on linen, ~ 23” x 33” stapled to a stained lightweight wood top frame about 24” x 1.5” and hung with yarn connected to a small nail on each side that used to hang from a decorative hook placed right above the electrical box. Advantages: disguises the electrical box but still permits ease of access. Framing support is only above. Can be configured with any dimensions so it covers just what you want it to. Could be a piece of decorative printed fabric, batik, painted silk, embroidery, etc.

The most common approach is to hang something in front of the panel. My panel is also in the front entry hall and so I have a large picture in front of it. In my experience I almost never need to access the panel since my electrical system is more than adequate for my electrical needs and so I have only had to reset a breaker once in three three years. I had more frequent occurrences before I remodeled and got a new panel because I would forget that my microwave and toaster were on the same circuit and so I would have to reset if I used at the same time.

Because you also have the switch next to it a picture isn't really a solution. Either move the switch which is somewhat of a hassle since you have to repair the drywall OR use @Lynne Om (9A, New Smyrna Beach,FL) 's suggestion and use a lightweight hanging of some kind. I have hung some fabrics in my home including a vintage kimono and a small embroidered hanging my mother did.