I have bought a laptop that was German (I’m not, I use an English keyboard), and I have a clean installation in English as Win 10 OS language and Greek loaded as an additional language pack. Both use a QWERTY layout, whereas German uses QWERTZ. To maintain my keyboard habits I physically flipped the Z/Y keys to have the alphabet keys in place (and re-tagged the 4 keys with the basic punctuation marks in the familiar QWERTY positions - I am putting this in parentheses because if I solve the first issue, read more, this will follow). Apart from the alphabet keys there are more than a dozen keys that differ (such as the shift numbers and others at the keyboard extremities). Those I don’t normally type “blind”, I look for them and press the key, as tagged. In order not to re-tag physically all the keys and make a mess of my laptop, I used Microsoft’s Keyboard Layout Creator to match the key codes with the key tags. To save myself retyping all the keyboard codes in basic, shift and AltGr shift combinations, I originated my custom keyboard with the German layout and changed only a couple of keys that I physically replaced, the Z/Y and the punctuation marks above. I saved the layout as English Language Layout and everything has been working fine: it is available as an English language alternative keyboard, I type what I see on the keys (wysiwyg) and spellchecks properly identify the language.
Not in Blender, not in parts of Blender anyway: In the viewport pressing Z which normally restrains along the Z-axis, restrains the Y and vice versa. But when I type text in a text file in blender Z is again Z… Somehow on occasions gets the blender key input at a lower level than the keysetup from Layout Creator, ignoring the setting that this keyboard is an English variant.