If you want to use different IP addresses then that is over my head, only had to worried about it ones myself.   But if you are trying to bridge them on the same IP then it should work,   And sorry, I told you to use wordpress as user and password but forget that, just leave them blank and they defaults to root with blank password. Make sure password in the MariaDB is set to 0 eg blank password, its only if you have changed it and the username you have to add it to the WP con