Logitech Gaming Software (LGS) shares the profiles between your G-Series keyboard and your gaming mouse, so no manual profile linking is needed. Macros and keystrokes you configured for your G-Series keyboard can be assigned to your gaming mouse, and mouse button presses you configured for your gaming mouse can be assigned to your G-Series keyboard.
NOTE: Certain mouse-specific buttons, like DPI Shift, can only be used with LGS-compatible mice. If you assign a G-Key on your keyboard as DPI Shift with a non-LGS mouse, the button will have no effect. Most other button presses, like Left and Right Click, can be assigned to your G-Keys.