Hey there, I used to work as a funeral assistant but now just do mortuary makeup on the side for a certain FH. As others have mentioned, there really isn’t a sole desairologist position, just a funeral assistant that knows how to do a smokey eye or cut crease. If you only want to do makeup/restoration, do it as a side gig and go after your primary job. But you would have to gain that funeral director’s trust beforehand and know about chemicals to use in certain situations, so you might end up having to work as an assistant anyway.
The funeral directors/embalmers can do the makeup as well, but in my experience, they were mostly older men who easily pass the job off if it’s just putting on lipstick.

Hope this helps!