there are no plans to schedule 'copy database'
If database_X8 is static (and if YOU know the structure of it)
this “copy database_X8 (old structure) from server_X8 to database_K2_raw (old structure)”
.. could be done by a 'notifications service' job executing CREATE DATABASE and CREATE TABLE statements.
Also you should try if the CONCAT_WS error still occurs. With recent versions we handle most differences between server versions.