Just Another Rotten Flesh to Leather Mod
This mod provides players with the ability to convert rotten flesh into leather. Depending on the difficulty setting (available only in Forge and NeoForge versions), the conversion recipe may vary.
Standard Mode
When the normal difficulty level is enabled, you can simply smelt rotten flesh in a furnace or smoker. Each unit of rotten flesh turns into one unit of leather.
Hard Mode
In the more complex version of the process, preliminary preparation of the raw material is required. First, rotten flesh needs to be turned into prepared flesh using a crafting table.

After this, the prepared flesh can be smelted in a furnace or smoker to obtain leather.