Is it possible to create keyboard shortcuts for applying MULTIPLE/DIFFERENT effects?
Click in the Menu Bar on “Final Cut Pro”. A pull down menu opens, then click on “Commands” then “Customise”
A window will open with all available commands possible. Many won’t have a shortcut and you can set keyboard shortcuts for them. Mind the search bar in the top right corner. 

I suggest to duplicate the Default command set before start changing. 

If this is not enough then you could look into make a command recording with Automator.