Found a way to get ALL pages at once into ONE page: https://github.com/NoahY/q2a-book BUT I must check the code again, it only takes 100 out of 560 questions in my test, "only hottest", so does not include all posts.
Update: I need to modify the q2a-book plugin because it only displays questions with answers. Here is the fork with the implemented changes: https://github.com/q2apro/q2a-book
Note: I am sure that this "solution" is mostly for small sites. If you have 100k posts you might run into memory issues.
Another way is to use a downloader software: https://www.httrack.com and then upload the HTML files to the server.
Any other option? Post it as a comment :)
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