Stir oats, flaxseed, chia, cinnamon, and salt together in a large bowl.
Warm peanut butter and honey in the microwave for 15–20 seconds to loosen, then whisk in vanilla.
Pour the peanut butter mixture over the dry ingredients and mix until evenly sticky.
Fold in the mini chocolate chips until distributed.
Scoop about 1 tablespoon of dough and roll into 1-inch balls. Roll in coconut if using.
Chill for 10 minutes to firm up, or enjoy right away. Store chilled in an airtight container.