Two extra twiddles.

I don't know if phantom power is an issue - as for condenser mics. This is usually not a nationality but an age issue - modern phantom power is 48 volt but it wasn't always.

Second, if you have a low powered device (like a preamp) you should be able to get in your home town, an inverter, to power say a mains TV off a car battery. The inverter will produce the right voltage and frequency, (same as local mains) within limits. Most inverters the frequency and voltage are both affected if you take too much power.

When you get to your destination, borrow a car battery or a SMOOTHED 12 volt power supply and then you use that to power the inverter.

Don't try it with power amps.