The latest versions of WhatsApp's CRYPT format (crypt5, crypt7, crypt8, crypt9, crypt12 file extensions etc.) are heavily encrypted, so in order to work with the data inside you will first need to use tools that convert these files to its earliest format - CRYPT. In order to do that you will need to first convert CRYPT7 to CRYPT.
After that you can use programs and websites like Whatsapp Xtract or WhatCrypt tools to export the chat backups from WhatsApp Messanger (*.crypt files) and save them as in a HTML form which when viewed using a web browser will look exactly like your WhatsApp (CRYPT to HTML conversion).
Microsoft Word and other word processors nowadays accept HTML files, so you can open/import them to these programs and save in the DOC/DOCX format as documents. They will probably look similar to WhatsApp, because the HTML is heavily formatted. You can also try some of the HTML to DOC converters.Open CRYPT7 file Open DOC file
Online service for WhatsApp databases
A database extractor for WhatsApp Messenger