Hi @JessicaZh2,
Interesting question, and I'm curious to learn more about Adobe's data deletion policy.
We've helped many users export their Workfront data and documents using our Workfront Snapshot and optional Workfront Snapshot Viewer solutions, but I don't recall anyone asking about then deleting the data from Workfront. Now that you mention it, though, we do also have an (unlisted) "reset environment" tool that deletes all user-entered data. We normally use it only on preview and/or sandbox environments for testing purposes, but technically, could repurpose it to meet your requirement.
Regards,
Doug