Using horizontal flip in the game engine can look odd—take the knight unit for example. When facing right, the knight holds the sword in the left hand and the shield in the right. But when flipped to face left, it becomes reversed: the sword is now in the right hand and the shield in the left, which looks incorrect.

yep maybe is a little bit odd, but is the standard on 2d sprites, normally you just flip the orientation when you wanna face the opposite direction, normaly theres no point on redoing the sprite to math the sword and shield hand.