You can buy one of Trixel's models together with its rig.
3D artist and animator Trixel showcased his skill in a 3D model of Alastor from Hazbin Hotel he made in Blender. You can see this signature smile in one of the rigging tests the artist presented:
This is the second version of the model, still a work in progress. If you're interested in what Alastor looked like before, there are plenty of images on Trixel's X/Twitter.
The best news is you can buy the old model with its rig for Blender 4.0+ on Gumroad, and when the new version is completed, those who have purchased it will get the improved one for free.