So you’re saying you’ll hook up the harddrive to the TV via USB?
USB harddrives are the same everywhere, what’s different is the electricity supply. You’ll need to get an adapter or perhaps a new supply cable at an electronics store. You might be able to get away with a USB harddrive that draws from the device it’s plugged into.
Also know that the electrical current in Spain has a habit of fluctuating in a way that can damage electronics with cheap power supplies.