Wortier is a word for a fantastical profession about magical books as you've mentioned, coined by the author Alexander Wales of the fantasy story This Used to be About Dungeons. He also coined other words like entad, cartier, henling etc. It is common practice to coin new words for worldbuilding in fantasy and science-fiction. Here are some usages of the word wortier (and also entad for unique magical items) in his story to have an idea:
Though the book was thin, it was immediately obvious why: the thing was infused with a very heavy wortier magic, such that the relatively few pages would reconfigure themselves to the touch of the reader, or in this case, shopper. There were manifold divisions of the entads, and they could be sorted by their form, their general magic, their specific magic, the store they belonged to, or their price.
“No, the value in this room is in the other books. You can just look at the spines and see they’re in no language you’ll have heard of. There are translation entads, or a wortier, who could translate them though, usually. Depending on what we have here, we might be looking at maybe fifty rings apiece.”
“I think they’d want to know about this one,” said Mizuki. “But I guess you can just have a wortier copy your official dungeon report and send it that way?”
This Used to be About Dungeons by Alexander Wales - royalroad.com
Wortier in town wortier in the citation from Agricultural Workers in the Class Structure (by Howard Newby, 1972) appears to be an erratum and it should be worker:
...to put the farm worker on a level at least with the town worker...
Note: OED lists entad as an adverb but it is a rare word used in anatomy and zoology, meaning "On or towards the inner side or interior of; in or into a position nearer to the centre of". It is unrelated to the word entad used in the story. FWIW, wortier is not listed in OED also.
