Enderyoink

Fully server-sided mod that allows endermen to pick up any block. They'll also drop unobtainable blocks that they're holding, such as bedrock and budding amethyst.

This is not done via a datapack, it's done through mixins, so it's technically compatible with any mod. I did not test this with any mods however, and it almost definitely causes severe issues with many, so do NOT install this mod on anything you care about!

I might update the mod to more versions later, but don't count on it, as it was just made for fun and for practice.