Copy config.php for "Migrating to a different server"?

[tomcat-xx]

In documentation for "Migrating to a different server" in step 4 (and in referenced "Backup" and "Restoring backup") it is described to copy config files / folder. Im wondering about that because of some entries in config.php:

1. datadirectory: Also in step 4 it is said that "Depending on the original installation method and the OS the files are located in different locations". But location of data files is stored in config.php and with copying it to new installation I would overwrite location setting. So either I have to copy config.php, so use same location as before (if just entry in config.php is containing it) and then also copy data to that folder.
2. dbpassword: New database has different password than old. So with overwriting config.php acces should not work anymore, or?
3. version: I did migration to upgrade NCPI, as direct update did not work in that case. So target has different version and at least displayed version would be wrong.
4. Other entries? So far I did migration without copying config.php, nextcloud came up but I did not dare to really switch to new one. Maybe other entries will cause issues.