wmi ExportVirtualSystemEx and UI export

dears

recently I develop WMI for import/export a vm from hyper-v in c#

but i find a subtle question between ExportVirtualSystemEx  method and export vm via UI(right click)

those folders are exported via ExportVirtualSystemEx  has a config.xml file under root folder, but another method.

the most interesting thing is those folders are exported via right click are unacceptable by ImportVirtualSystemEx method.

any idea?

thanks