You should do it however you’d like. Especially if it’s just paint. You can always repaint it. When I bought my house, there was an accent wall (a full mural) painted in the master bedroom. I hated it. I felt so horrible for hating it, because at closing the former owner’s wife told me she hand painted it. It was literally the first thing I changed when I moved in.
That being said, I do have 2 accent walls that I painted in other rooms. Both are a dark blue. I know someone above thought dark colors look dated, but I think mine look pretty snazzy. I picked that color with a purpose in mind. The other walls in the room are white, and the trim is tan. On the one in my office, I have a huge 3.5ft x 5 ft sepia print of a beach photo hanging on it. There is a silver frame. Looks amazing with the whites and tan and blue, and there’s a gray couch right under it which plays right into the silver frame.
The other one is in my game room, and in front of it is a tv, speakers, bookshelves. Above the TV we have a landscape photo hanging from Niagara Falls, which shows them all lit up with blue lights. The colors of the falls look amazing against the blue accent wall. Both rooms have hardwood floors, and off white/ivory colored area rugs.
It took me going to about 50 different stores, but eventually I found curtains in the same exact color blue. We have them hanging in those rooms to help tie the blue in with its surroundings.
Those same blue walls would look horrible at, say, my parents house.