If you’re seeing errors in the Google Search Console for Structured Data > hatom (markup: microformats.org) for missing “author / entry-title / updated” values – these errors are not from meta tags or Schema markup.
There have been several markup formats supported by Google over the years, and your theme templates may include older (and incomplete) hatom / microformats markup. You should contact your theme author to have them fix or remove the incomplete hatom / microformats markup, or try and Remove / Fix ‘hentry’ Errors in your Theme Templates yourself, using a WordPress filter (provided your theme templates use standard WordPress filters).