How to see changes inside Paragraphs or Field Collections with Diff
You have to install and enable the Diff module.


  This module adds a tab for sufficiently permissioned users. The tab
  shows all revisions like standard Drupal but it also allows pretty
  viewing of all added/changed/deleted words between revisions.


Nothing else is needed.

Given a simple paragraph with a boolean field and a text field, if oyu change the textfield uou will get someting like this: