Preheat the oven to 425°F (220°C).

In a mixing bowl, combine flour, baking powder, garlic powder, and salt.

Cut in the cold butter until the mixture resembles coarse crumbs.

Stir in the cheddar cheese and buttermilk until just combined.

In another bowl, mix together crab meat, cream cheese, mayonnaise, Old Bay seasoning, parsley, and lemon juice until well combined.

Scoop a tablespoon of biscuit dough and flatten it in your hand.

Place a tablespoon of crab filling in the center and fold the dough over to seal it.

Place the filled biscuit on a baking sheet lined with parchment paper.

Repeat with remaining dough and filling.

Bake in the preheated oven for 12-15 minutes or until golden brown.

In a small bowl, mix melted butter, lemon juice, lemon zest, and garlic powder.

Brush the warm biscuits with lemon butter before serving.