Você pode alternar o US para Dansish para o grego, adicionando:
-layout "us,dk,gr"
Assista: setxkbmap -model logicordless -layout "us,dk,gr" -option "grp:alt_shift_toggle"
Ou edite /etc/X11/xorg.conf.d/90-custom-kbd.conf
Section "InputClass"
Identifier "Logitech Cordless"
MatchIsKeyboard "on"
Option "XkbModel" "logicordless"
Option "XkbLayout" "us,dk,gr"
Option "XKbOptions" "grp:alt_shift_toggle"
EndSection