Best to post development questions to zotero-dev — we try to keep technical discussions there.
Scaffold doesn't support export translators. You can edit a file in the 'translators' folder of the Zotero data directory and restart Zotero, or you can develop against translation-server.
I guess you need Scaffold, tick the export box, but then what script you need to write?
From that discussion https://github.com/zotero/translators/issues/773 I could see it exist an export translator but last comits and news are from 2014 ; and I don't have practice with this. See https://github.com/zotero/translators/blob/7a5f96a5354770fcc0524e9c5bcdcbaca3783149/CSV.js
Scaffold doesn't support export translators. You can edit a file in the 'translators' folder of the Zotero data directory and restart Zotero, or you can develop against translation-server.