Public service message: France and other French speaking countries like Belgium (that's me) use the Azerty keyboard layout instead of Qwerty. This means your pretty WASD control scheme will look something like ZQSD would look on an international keyboard.
This mapping works both ways. So you can solve this issue by allowing people to use the ZQSD input scheme as well as WASD.
There is also the Eastern European Qwertz layout which doesn't interfere with WASD but will still mess up hotkeys.
its easier to change keyboard layot (eg. <left alt> + <shift> for EN) than make localized hotkeys i would say
this is true as the only data you could get from Key presses are integer values used by blizzard themselves (-1 to 98), so you are unable to use Scancodes or read the registery entries of your OS for your used Keyboard-layout
the only way you could "do" it would to ask what layout you use ... and this would start annoy ppl using standard QWERTY/Z layouts :/