Cut a deep pocket lengthwise into each salmon fillet without slicing all the way through; brush the outside with olive oil and season with salt and pepper.
In a bowl, gently combine lump crab meat, softened cream cheese, bread crumbs, mayonnaise, mozzarella (if using), Dijon mustard, Worcestershire sauce, green onions, parsley, garlic powder, Creole seasoning, and lemon juice.
Fill each salmon pocket generously with the crab mixture and press edges gently to secure the stuffing.
Preheat the smoker to 225°F using applewood or alder wood chips for mild smoke flavor.
Place the stuffed salmon skin-side down on the smoker rack and smoke for 45 to 60 minutes, until the internal temperature reaches 145°F; brush with olive oil or melted butter during the last 10 minutes.
While smoking, prepare the garlic lemon sauce by melting butter with heavy cream, garlic paste, lemon zest, and Creole seasoning in a saucepan until smooth.
Remove salmon from smoker, let rest for a few minutes, then serve with lemon wedges and drizzle with the optional garlic lemon sauce.