How to make a button animation in menu

I made a game scene with menu basic options like play, settings and so on
but for let this more attractive to the user i want a simple animation for this buttons.
i don’t want a hover or onclick animation i want the buttons to repeat the animation while the user is in the home scene
the animation can be color change or the button changing his size or position in the screen (i don’t know the right name for this i imagine like a wink effect)
i don’t know if it’s helpful but the it’s a 2D project

I guess a handy animation plugin is what you want.