The latest German magazine Mac & i has a nice review on Mail Archiver X.

Because the magazine is paid I can't show the review here. Here is a summary:

  • Archiving & Storage: Saves emails locally in formats like MBOX, PDFs, or a Valentina-based database, freeing up server space.
  • Compatibility: Works with Apple Mail, Outlook, Thunderbird, and IMAP accounts.
  • Selective Archiving: Filters by date, age, or folder, excluding duplicates.
  • Automation: Supports scheduled archiving with reports.
  • Search & Backup: Offers robust search tools and export options, with the ability to re-upload to IMAP.

Efficient and easy to use, it processes large mailboxes quickly and is ideal for safeguarding emails.