ducknukam wrote:If MariaDB is installed from XAMPP then a daemon from XAMPP is responsible for stopping MariaDB (possibly improperly).
Well, not exactly. The XAMPP control panel is just a piece of software to centralize the prozess commands into one single place.
But the control panel is not able to shutdown MariaDB properly, because the methods to stop a MariaDB Server would need Database credentials to fire a SHUTDOWN command, which can be changed by the user at any time and therefor destroy the ability to stop the MariaDB Daemon completely.
For that reason (and because it was never a problem for early MySQL Servers) the control panel simply kills the mariadb process. But that seems to do some harm to modern MariaDB Daemons.
ducknukam wrote:if I really want to deploy MariaDB standalone, how would I integrate it with XAMPP, I mean configuration wise? Or it would work out of the box?
MariaDB is coupled relatively loose to other XAMPP components. You would only need to recreate/reinstall the phpmyadmin database. And you need to configure MariaDB Server to listen on TCP port 3306 which can be done by the MariaDB installer.
You cannot start or stop any standalone MariaDB servers from the XAMPP control panel, so you need to use the MariaDB internal methods with mysqladmin shutdown, or by windows service.