I have to move blogs from a WordPress site to another WordPress site but with applied filters.

Details:

Every blog has an author as we all know it but this time when I move the blogs, I only want to tag them in the article rather than showing 'by this_author'. I have the database, I have migrated the whole site and I'm able to access the site without any problems. The blogs are also visible along with their author name but that's not what I'm trying to do.

I would like to know if there is a way I can remove all the 'posted by this author' to just their names in the article as a tag. I'm working with over 1000+ authors, so I can't take the manual route.

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