Looking for an OpenSource e-mail export tool

Hi everyone, I am looking for a free/opensource email tool to help me export my emails from my inbox.

Here is some information:

• I receive several requests per day via email (IMAP)
• I move these requests to a subfolder (IMAP).
• There are over 1000 emails from different people.
• However, the subfolder also contains email requests from the same people. (Duplicate email addresses.)

I am now looking for a free tool that scans the existing and new emails and exports the name and email address, preferably into a Google list or, for example, directly into a newsletter, CRM tool.

Perhaps there is also a newsletter tool that can pull all emails from my IMAP subfolder and then check them for duplicates and manage them?

This ensures that no duplicate email addresses are included.

Is there a tool, software, newsletter tool, listmonk, Keila, Matuic, make.com, zapier.com, github etc. that can do this?

Thank you all!