sysvorOrt /home/michi # emerge --config =dev-db/mysql-8.0.27


Configuring pkg...

 * Looks like your data directory '/var/lib/mysql' is already initialized!
 * Please rename or delete its content if you wish to initialize a new data directory.
 * ERROR: dev-db/mysql-8.0.27::gentoo failed (config phase):
 *   mysql data directory at '/var/lib/mysql' looks already initialized!
 * 
 * Call stack:
 *     ebuild.sh, line 122:  Called pkg_config
 *   environment, line 3048:  Called die
 * The specific snippet of code:
 *               die "${PN} data directory at '${MY_DATADIR}' looks already initialized!";
 * 
 * If you need support, post the output of `emerge --info '=dev-db/mysql-8.0.27::gentoo'`,
 * the complete build log and the output of `emerge -pqv '=dev-db/mysql-8.0.27::gentoo'`.
 * The complete build log is located at '/var/tmp/portage/dev-db/mysql-8.0.27/temp/build.log.
 * The ebuild environment file is located at '/var/tmp/portage/dev-db/mysql-8.0.27/temp/envionment'.
 * Working directory: '/var/tmp/portage/dev-db/mysql-8.0.27/empty'
 * S: '/var/tmp/portage/dev-db/mysql-8.0.27/work/mysql-8.0.27'

In diesem Fall ist die MySQL Installation und Konfiguration schon einmal durchgeführt worden.
Infos zum Thema gibt es hier: https://wiki.gentoo.org/wiki/MySQL/Startup_Guide/de