On start-up, my bungee server has an error with the latest version of UTF8:
20:27:33 [SEVERE] [LuckPerms] Failed to init storage dao 20:27:33 [SEVERE] java.sql.BatchUpdateException: Unknown character set: 'utf8mb4' 20:27:33 [SEVERE] at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 20:27:33 [SEVERE] at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) 20:27:33 [SEVERE] at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 20:27:33 [SEVERE] at java.lang.reflect.Constructor.newInstance(Constructor.java:423) 20:27:33 [SEVERE] at me.lucko.luckperms.lib.mysql.jdbc.Util.handleNewInstance(Util.java:425) 20:27:33 [SEVERE] at me.lucko.luckperms.lib.mysql.jdbc.Util.getInstance(Util.java:408) 20:27:33 [SEVERE] at me.lucko.luckperms.lib.mysql.jdbc.SQLError.createBatchUpdateException(SQLError.java:1163) 20:27:33 [SEVERE] at me.lucko.luckperms.lib.mysql.jdbc.StatementImpl.executeBatchInternal(StatementImpl.java:1060)
I have checked and I am sure that my MySQL database is up to date.

MySQL server version? Looks like it's not actually the latest version

Yep, you need to update your MySQL server version.