Default [Q] Different language ROMs

Greetings guys,

I'm just wondering if I can apply an English ROM (custom or official) to a German 7 Pro? What happens with the keyboard layout then, as for those you don't know, on the German devices the Y and Z letters are cross-put. So what would those keys press when I got the English ROM; would they revert to English layout or those are hard-coded so the physical keyboard would continue registering the German layout?

Thanks in advance!