SellCloud recommends setting up Websites(files) backup using SFTP and Database backups using remote connection/SSH for your WordPress websites whenever possible.
Database Export
How to Export a Database Using phpMyAdmin
How to Export a Database Using Adminer
How to Export a Database Using Adminer Plugin
How to Export a Database Using the Command Line
How to Back Up MySQL Databases with AutoMySQLBackup
Database Import
How to Import a Database Using Adminer
How to Import a Database Using Adminer Plugin
How to Import a Database Using phpMyAdmin
How to Import a Database Using the Command Line
Wordpress folders & files Export