Line a baking sheet with parchment paper; set aside.
In the bowl of a food processor fitted with the metal blade, process dates, plums, sunflower seeds, pumpkin seeds, chocolate chips, blueberries, cocoa powder, salt and water until almost smooth.
Place the coconut and chia seeds for rolling in separate shallow bowls. Fill a medium bowl halfway with cold tap water. Dip your hands in the water and shake off any excess (this will prevent the balls from sticking to your hands and ensure that the topping sticks to the ball). Roll a heaping tablespoon of mixture into a 1½-inch ball between moistened palms, roll the ball in either the coconut or chia seeds, and then place it on the prepared baking sheet. Repeat with the remaining dough, moistening your hands as necessary and spacing the balls about 2 inches apart. Place the balls in the freeze to chill for 2 hours.
Wrap each ball individually in parchment paper or bakery tissue paper, place in a sealable plastic freezer bag and keep frozen until ready to eat.