How to add an EFF from Product item master as a field in Manage spoke systems.

Summary:

Business runs the job - "Product Hub Publication Job" using the Manage spoke systems for publishing few fields as a payload for integration.
As an enhancement, a new field has to be added to that available spoke system. This field is an EFF and is not available in Manage spoke system page.
Please suggest on how to get that field in the manage spoke system page and add it.

Also, if we need to create a new Spoke system. how to create it.

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