Hi Aternos Team, can you please add the following plugin?
Plugin name: Essentials
Please scroll down a little bit and click the 1.15.2 version because the one you have posted is the older version 
Plugin link: Spigot ProtocolLib
If you dont want to scoll down and try find the other version thats fine! Heres the link that they posted.
Direct Download Link: https://build.true-games.org/j…arget/ProtocolSupport.jar 
Description: It is ProtocolLib for 1.15.2 so that 1.8.9 can connect to my 1.15.2 server.
Thank you!