MVS subprojects inherit their current property group from the remote system under which they are defined. If you change the current property group for the system or change property values in that property group, they are propagated to the MVS subproject. However, you can also assign a different property group to a project or subproject to differentiate its property values from those of the remote system.
The z/OS Projects or Enterprise Projects view provides an option to turn off file extensions for files in MVS subprojects. From the drop-down menu, click Show > MVS File Extensions. See z/OS Projects view for more information about this option.