QWERTZ and Delete Key

If you’re using sway, you can use a custom keyboard layout by adding this to .config/sway/config:

input "1003:8258:MNT_Reform_Keyboard" xkb_layout my-layout

This will read the file .xkb/symbols/my-layout, in which you can remap keys. Paste the following content in that file:

default partial alphanumeric_keys
xkb_symbols "basic" {
        include "de"
        name[Group1] = "MNT Reform German (with HYPER as DEL)";
        key <RWIN> { [ Delete, Delete, Delete, Delete ] };
};

Then reload sway with Super+Shift+C. Now you will have a QWERTZ layout with the HYPER key producing DEL.

You can look up the symbolic key names (like <RWIN>) in the file /usr/share/X11/xkb/keycodes/evdev.