In a large bowl, combine flour, garlic powder, onion powder, paprika, salt, and black pepper. Mix well.
Dip each piece of chicken into the flour mixture, coating it evenly, then into the beaten eggs, and finally into the panko breadcrumbs, pressing gently to adhere.
In a large skillet, heat about 1 inch of oil over medium-high heat. Once hot, carefully add the coated chicken pieces in batches, avoiding overcrowding. Fry for about 3-4 minutes on each side or until golden brown and cooked through.
Remove the chicken from the skillet and place it on a paper towel-lined plate to drain excess oil.
In a separate bowl, mix together the mayonnaise, sweet chili sauce, and sriracha until well combined.
Toss the fried chicken pieces in the sauce until evenly coated.
Serve immediately, garnished with sliced green onions.