Preheat your oven to 425°F (220°C). Line a baking sheet with parchment paper.
In a large bowl, whisk together flour, baking powder, baking soda, garlic powder, salt, and black pepper.
Stir in the shredded cheddar cheese until well combined.
In a separate bowl, whisk together buttermilk, melted butter, and egg.
Pour the wet ingredients into the dry ingredients, mixing until just combined.
In another bowl, combine lump crab meat, green onions, mayonnaise, Dijon mustard, and Worcestershire sauce. Gently mix until incorporated.
Using a biscuit cutter or your hands, form the cheddar biscuit dough into rounds about 1-2 inches thick.
Make an indentation in each biscuit round and spoon the crab mixture into the center. Fold the dough over the filling to encase it and reshape as needed.
Place the stuffed biscuits onto the prepared baking sheet. Bake for 15-20 minutes or until golden brown.
While the biscuits bake, mix melted butter, lemon juice, and lemon zest in a small bowl.
Once biscuits are done baking, remove them from the oven and brush them generously with the lemon butter.