Not airfryer related but we always cook beef in our slow cooker
Cook on Max 4.5/5hrs cut a few carrots in big chunks place in the bottom sit joint on top
No liquid required
Leave alone,once cooked /cool/place in fridge overnight then ready to slice
If needing it hot place slices into a oven tray cover with heated gravy place in preheated oven then serve
The best/moist/tasty beef ever,every time,same cooking method with a leg of lamb maybe less cooking time than the beef depending how you like it,ours 3.5/4hrs