Hello Tracy,
You can enable Network Configuration Assistant plug-in z/OSMF "General Settings" task. In "General Settings" task the plug-in name is properly identified. This is.a recommended way to manage plug-ins (i.e. enable/disable). z/OSMF needs to be recycled to pick up plug-in configuration changes.

You can also use z/OSMF parmlib member to enable plugins that existed prior to z/OS 2.5. You are right that in z/OSMF parmlib member you need to specify COMMSERVER_CFG to enable network configuration assistant.
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Hiren Shah Senior Technical Staff Member (z/OSMF)
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