Or if you want to be sure no Reader attributes are used on the Writer feature types you can use the BulkAttributeRemover (mask geodb* in this case) to remove all reader format attributes.
@adriancoelho You can right click the Reader\ Feature Type Properties\ Format Attributes check the geodb_feature_dataset to expose this attribute. Afterwards you can delete this Attribute in an Attributemanager --> no Feature Dataset will be created.