Split WordPress into 2 servers (one exclusive for database)


I already have a WordPress site installed with Easy Engine and I need to migrate the database to a unique server to balance the load.

I followed the steps in this tutorial but it did not work:

All these settings are made on the server that will host MySql?

I made a Snapshot of the current server and created the new server with this image, to already have the Easy Engine and database, then I ran the tutorial settings but it still connects with MySql of the old server.

Is this the best way or is it better to use another way? What would be the best way?

Is it necessary to make any changes to the wp-config.php file? I tried to change the host to the IP of the new server but it has a connection error with the database.

Thank you