Help with turning a .jar file to .mcr file

So I want to be able to make my mods DragonCraft and DragonMaster's Winter be available for 1.12.2. Both mods have been lost or deleted but I have the .jar files and I would like to import them into Mcreator 1.8.3. Klemen if you are reading this could you send me the .mcr files for both mods if you can make a .jar file into a .mcr file.