The title is self-explanatory, the only plugin I know that currently works is NoAI but it is very outdated for the server that I run. There could still be a plugin out there that works, but I tried searching for everything I could.
First of all please format it better.. https://bukkit.org/threads/read-me-first-plugin-requests-guide.81209/ Also.. What version? 1.12? 1.8? 1.13? 1.14? All mobs should be just still? In 1.8 they can still jump though