This is a list of use cases achievable using xkb configuration.
https://geekhack.org/index.php?topic=53137.msg
type "SHIFT+SUPER" {
modifiers= Shift+Super;
map[Shift]= Level2;
map[Super]= Level3;
map[Shift+Super]= Level3;
preserve[Shift+Super]= Shift;
level_name[Level1]= "Base";
level_name[Level2]= "Shift";
level_name[Level3]= "Super";
};
key <AD02> {
type= "SHIFT+SUPER",
symbols[Group1]= [ w, W, NoSymbol ],
actions[Group1]= [ NoAction(), NoAction(), RedirectKey(key=<UP>, clearMods=Super) ]
};