Datapacks for unused mobs

There are many mobs from Minecon/Minecraft live votes that were so cool and it's so disappointing that they did not get voted. I think it would be great if we could get data packs that add at least just the basic idea of the unused mobs, like the mobs from when the phantom was voted, the Moobloom and Iceologer, and just any mobs that we know we will never have a chance to have in the actual game again.