Witchery mod didn't get any updates for the last 2 years or so, and the author seems to be gone. Im willing to pay 100$ for a fully working 1.12.2 port of the Witchery mod. If the job gets too hard we can negotiate about raising the cost of the job.
P.S. The project must get open-sourced after the release, or in case of developer abandoning the project.
From what I saw, most of the methods he had used were gone XD