Reader
Magento\ImportExport\Model\Export\Config\Reader
What it does
This class reads and parses export.xml configuration files from Magento modules to define available export entities, entity types, and file formats.
It extends the framework's filesystem config reader and specifies how to merge multiple export configuration files by identifying entities by name, entity types by entity+name combination, and file formats by name.
Developers use this indirectly when the system loads export configurations during the import/export functionality initialization.