I am trying to find out a way to compare 2 version of document without using MS Office.
Is there any plug in /add-on/edittor/connector available to do that?
You can compare two files side by side and view the differences with Arender (View any document anywhere - ARender ).
I only know of commercially-available add-ons that do that. Here's one: VirtualViewer HTML5 Accelerates Workflow with Document Comparison (4/17/18) | Snowbound Software
Have you thought about the different possibilities via Solr. It seems to me that in the latest versions, this one adds a fingerprint on each file. You then have the opportunity to search by fingerprint and compare the two results.
Document Fingerprints | Alfresco Documentation
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