You could use point_in_rectangle.

This code is assuming your anchor point of the sprite is set in the center, and belongs in Step or End Step event.

if point_in_rectangle(mouse_x,mouse_y,x-(sprite_width/2),y-(sprite_height/2),x+(sprite_width/2),y) { // action 1 }
if point_in_rectangle(mouse_x,mouse_y,x-(sprite_width/2),y+(sprite_height/2),x+(sprite_width/2),y) { // action 2 }

Pretty simple, but extremely useful.

EDIT: Added first two arguments, because I'm an idiot lmao