"An action, which can be assigned to standard shortcut" - I mean an action, which can be found in the list in:
System Settings > Shortcuts and Gestures > Standard Keyboard Shortcuts.

E.g. (such actions): About Application, Copy, Cut, Paste, Undo, Redo and so on.

Q: Is possible to invoke a standard keyboard shortcut (or an attached action) via D-Bus command? If it is possible, how to do this?

It is possible to invoke a global keyboard shortcut.
E.g., the following command invokes a global shortcut "Maximize Window" of KWin component:

Code: Select all

qdbus org.kde.kglobalaccel /component/kwin org.kde.kglobalaccel.Component.invokeShortcut "Window Maximize"

To the best of my knowledge this is not immediately possible. However what you could do instead of issuing the command via D-Bus is "simulate" the keypress which should trigger the shortcut if you are focused in the correct application.

xte can be used for these purposes.