Replacing wall sconce (that has on/off swtich) with ones that do not. Need options for control
You have options, they actually make smart light bulbs you can power on and off with an app, but beyond that you can always find a wall scone made of aluminum and drill out a canopy switch, connect it to the positive on the fixture and problem solved. More invasive would be snaking a 14/2 to a future switch box location, install both black and white to the switch (mark the white wire with black tape to prevent  accidents in the future. Then you need to connect the feed wire (the positive wire that carrys the power to the light) to one side of the new wire, and the positive going to the light fixture to the other side of the new wire. Hope this helps