Simply, FTFO means "Fight the Fuck On." It's a play off the Trojan phrase "Fight On," but gives it more of a kick (even though Trojans always go hard, it's just assumed they all Fight the Fuck On.)
in Romanian means pussy ( pizda ) but without the negative conotation. It is a bit archaical and not very frequently used. It's rather rural than urban!
Stai cu fofoloanca la soare!
means ad-literam:
You're staing with your pussy to the sun - you do nothing, you're wasting your time.