This link has a chart that can hep identify the critters scat. According to that chart skunk has the tapered end. Also the eggs give a clue. Possum are supposed to smash the eggs when they eat them, skunk leave them opened but intact. Skunks are supposed to lick them empty but those may show a baby in training.
https://www.abeepestpro.com/differences-types-of-pest-droppings-poop.htm
https://www.abeepestpro.com/differences-types-of-pest-droppings-poop.htm