Preheat oven to 350ºF/177ºC and grease a shallow baking dish.
In a large mixing bowl, mix together chopped shrimp, cream cheese, yogurt, bleu cheese, cheddar, hot sauce, garlic powder, and most of the green onion slices (save some of the green slices for topping after!).
Spoon into the baking dish and flatten with the back of the spoon.
Bake for 30 minutes or until slightly brown around the edges.
Top with extra bleu cheese, remaining green onion slices, and chives.