tt400 wroteNo, it will work. My phone is from Switzerland and I use and update it without a problem. Make sure you download the AFG model. You might have to root your phone to be able to access other firmwares, which might void your warranty.
All firmware of the exact same phone works without any issues, unless they're carrier based, but those still might work, but with extra bloatware installed.
It doesn't matter what region you install from. I have an N7100 Note 2 bought from here, it has ran firmwares from India, UAE, Switzerland and who knows where. As long as I have an N7100, I can install any N7100 firmware.
Flashing your firmware already voids your warranty, as the bootloader counts how many times the phone has flashed. Unless it's 0, your warranty is voided.