Hi,
an additional note:
For the standard config files (Engine/Game/…) you can use the predefined config hierarchy to override setttings per platform (no C++ needed in that case).
There is a list with the hierarchy and the order in which config files are loaded on the docs site here (under the Configuration File Hierarchy section ).
You can also find the most up-to-date hierarchy from the source code in the file Engine/Source/Runtime/Core/Public/Misc/ConfigHierarchy.h.
In your case, for platform specific config files you can use the following paths (item 8 in the list in the docs):
<PROJECT_DIRECTORY>/Config/<PLATFORM>/<PLATFORM><CATEGORY>.iniFor example on WindowsServer you can override Engine.ini settings in
Config/WindowsServer/WindowsServerEngine.ini
Kind Regards,
Sebastian