Begin by finely chopping the imitation or real crab meat into small chunks, approximately 2 cm wide. Set aside.
In a mixing bowl, soften the cream cheese using a spatula until smooth and pliable. Add the crab meat along with chopped green onion, soy sauce, sesame oil, Worcestershire sauce, sugar, garlic powder, and black pepper. Using a fork, combine everything thoroughly until the crab meat is evenly distributed and the mixture is well-blended.
Place one wonton wrapper on a clean surface. Spoon about ¾ tablespoon of the crab filling into the center. Lightly moisten the edges of the wrapper with water using your fingertip to ensure a proper seal.
Lift two opposite corners of the wrapper and pinch them together at the tips. Bring up the remaining two corners and pinch all points together, ensuring a tight seal at the top. Press along the seams to prevent the filling from leaking during frying.
In a deep, heavy-bottomed pan or Dutch oven, pour in the oil and heat it over medium heat until it reaches 325°F. Carefully lower the wontons into the oil in small batches, being sure not to overcrowd the pot. Fry each side for about 2 minutes or until golden and crisp.
Once cooked, transfer the crab rangoons to a wire rack or a plate lined with paper towels to drain excess oil. Allow them to cool slightly before serving.
Serve with a side of sweet Thai chili sauce or plum sauce for dipping.