yeah its not that easy... its not easy to find a mod can have the same features as a plugin does have.. i know there are some mods have different names, but have same features as a plugin does.
for an example "MySQL inventory" for Spigot but what i found is that there is no inventory mod for forge.. since cauldron/bukkit-forge is dead... its hard. so there is nothing i can do about that.
One more thing to add. I also tried to find to see if there is a mod that would allow forge to use any plugins from either bukkit or spigot.. but i couldn't find any.. i guess it dont exist... u know the idea of that came from "pore" for Sponge with plugins from spigot/bukkit... too bad theres none.