Wash the orange, apple, cranberries, and ginger thoroughly.
Slice the orange into rounds and remove visible seeds.
Core and thinly slice the apple.
Thinly slice the fresh ginger.
Pour apple cider, cranberry juice, and orange juice into a 5–6 quart slow cooker.
Add cinnamon sticks, cloves, star anise, and ginger.
Add orange slices, apple slices, and fresh cranberries.
Stir in 2 tablespoons maple syrup.
Cover and cook on LOW for 3–4 hours or HIGH for 1½–2 hours.
Stir in vanilla during the final 15 minutes.
Taste and add additional maple syrup only if needed.
Remove the cloves and ginger before serving.
Switch the slow cooker to WARM.
Ladle into heat-safe mugs.
Garnish individual mugs with orange, cranberries, or cinnamon sticks if desired.