I have made a package that can export notebooks to WordPress, which is also how the Wolfram Blog works. I have described my package here:
http://wolframlanguagereviews.org/2018/10/28/posting-notebooks-to-wordpress
You can see an example of an article here:
http://wolframlanguagereviews.org/2018/08/09/domain-decomposition-method-using-graph-coloring
You can get the package here:
https://github.com/cekdahl/wl-wordpress-xmlrpc-client
Unfortunately, it's not particularly easy to set up or use at the moment. WordPress 5 brought with it a regrettable change, the Gutenberg editor, which is incompatible with this approach because it doesn't let you store custom HTML. It will always try to change the HTML for you, even if you don't want it to. I solved this by installing a plugin which disabled the new editor and reverted to the one in WordPress 4, but even here there is the caveat that you must never use the WYSIWYG editor because if you do it will mess with the HTML.
To sum it up, I have written a solution that works well for me but it is not yet easy for others to use so you have to be prepared for some trouble if you decide to use it. So far, I know of one other person who has successfully installed it.