What is the best way to overwrite /wp-admin/ms-delete-site.php

Another alternative is to look at the hook map_meta_cap and remove the user’s capability to delete_site. If you have a restricted set of users or context when you want to allow delete_site then you can allow the capability.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)