Preheat oven to 400°F.
Cut the acorn squash in half vertically and scoop out the seeds.
Brush the squash with olive oil and season with salt and pepper.
Roast the squash cut-side up for 25-30 minutes or until fork-tender.
While the squash is roasting, cook the wild rice blend according to package instructions.
In a large skillet, cook the chicken sausage over medium-high heat, breaking it up with a spoon as it cooks, until no longer pink, about 5-7 minutes.
Add the chopped onion, mushrooms, and garlic to the skillet and cook until the vegetables are tender, about 5 minutes.
Stir in the diced apple, dried cranberries, and cooked wild rice blend.
Add the chopped kale to the skillet and cook until wilted, about 1-2 minutes.
Season the filling with nutmeg, salt, and pepper.
Scoop out some of the roasted squash flesh to make room for the filling, then fill each squash half with the sausage and rice mixture.
Top each filled squash half with toasted pecans and chopped sage.
Bake the stuffed squash for an additional 15-20 minutes or until heated through.