With the mouse it's easy: Right click on desktop -> Desktop Settings -> Layout -> Folder View -> Ok. Done.

How Can I get the corresponding command line action (kwriteconfig or similar)?

Can I somehow record it that action? And replay it later with bash?

You probably want to look into Plasma's Javascript interface for this - documentation is available on KDE Techbase.
Unfortunately while you can load the script into the appropriate dialog, it is necessary to press run manually to actually execute the script.
It is not recommended to use kwriteconfig either, as the Plasma Desktop configuration file may be overwritten when it exits - effectively wiping out your changes - and potentially causing future issues due to an inconsistent state.