The Xink platform supports Google Directory's custom field creation.
1. The client must create the custom field in Google Directory.
For example, You have custom field 'Hobby' in Google Directory.
2. Go to Xink Preferences > Fields and add the field in the following format "customField_CUSTOM_SCHEMA_CUSTOM_FIELD_NAME"
You can find more information here https://developers.google.com/admin-sdk/directory/v1/guides/manage-schemas