When we use dual monitors, we like to move the active windows between the monitors.
To add a keyboard shortcut for this in KDE.
Goto “System Settings->shortcuts and gestures->global keyboard shortcuts”
select the component “KWin”
Than, set as below.
Window to Screen 0 = Meta+Left and Window to Screen 1 = Meta+Right
Meta is the windows key.
Now, We can switch the applications to the monitors with the keyboard itself.