Hi @mandy6833! I feel your design woes with this one (I also have a big, bulky doorbell box). I've tried a couple of things, but my DIY hat wall was the thing that worked best. Basically hammer a few nails into the wall and arrange your hats, with one of them sitting on top of the doorbell box. It hides it perfectly! You could also build a box to place over the top and cover it up. Or get really hacky with it and do a piece of artwork on hinges like this!
I like Daniela's idea of hats. You could also hang a large, round basket over it, bottom-side out. Think of something dimensional that you might already have, such as a pottery bowl with handles. I bet you've got something around the house that could become an art piece here.
You can buy doorbell covers on Etsy to change the color/finish, ideally a dark wood. However, as far as doorbell boxes go yours is very nice and new looking so you could also lean into it with white decor. The clutter on the desk is the bigger issue than the box.