Never made it but Sausage maker has a high temp Smoked Gouda. Search SMF for a Brat recipe that sounds good. Add 1/4" diced apples. The amount should be around 20% +/- of the meats weight. Look for a low moisture variety like Fuji or Granny Smith. Add 10%, by weight, of the HT Smoked Gouda. Make a test patty. Add more cheese or whatever you think it needs and stuff the casing. This will be a Fresh Sausage and requires cooking at temps of 225 or higher.
I think the hint of smoke from the cheese would taste better in a grilled Brat rather than a full blown smoked Apple Cheese Brat...JJ