Combine softened cream cheese and mayonnaise in a bowl and beat with a handheld blender until combined and creamy.
Add in parmesan cheese, cheddar cheese, green onions, worcestershire sauce, and garlic powder. Blend together until combined.
Lay out a piece of plastic wrap (saran wrap) and dump the sliced almonds in the middle. Using the wooden spoon, try to form the cheeseball mixture into some sort of a ball (inside the bowl you mixed it in). Dump the ball on top of the almonds on the plastic wrap.
Use the plastic wrap to press the almonds into the cheeseball and to form into a better "ball" shape. Put on a plate and let sit in the fridge for 2 hours to firm up and the flavors to come together.
Serve with your choice of crackers