What about SEO plugins? Plugins who creating schema markup, the serps meta description, plugins who submit your content to your social media accounts? Hold on for a second......with the HCU algo google will see this as seo manipulation I guess ?
Better use only these so called fields plugins (or similar name) means under your posts in wp you have fields to fill out for serp meta description and add your schema markup, better us eonly schema plugin not editing serp meta description it will be mroe safe (my theory). Not use plugins to submit your posts automatically to FB, Twitter etc,etc.....google targets automatic plugins too with that demonish HCU update.
By the way, proof the ownership of content; when I have my author bio under each post on my site + my detailed about me page with contact, map, social profiles, a little content policy, is it not enough that I be the owner of the content? I no thave any idea of showing more proof- do you have one?
As far I know, (correct me) when you have a good prompt to let AI write or rewrite a new unique article, then AI is not the owner of that content-that is you.
Some bigger sites more media sites who allwing guest posts have an editorial page. Some have an ethic conduct page, an ethic conduct page is not a direct EEAT sign (more like an indirect signal).
For affiliates- better you write good content aligned with EEAT guidelines, example: your affiliate site has 100 posts of informational content and a section with 20 product reviews or 20 commerical posts about your single product you promote, that will be a good ratio- not the whole website full with product reviews.
Maybe add in your about me page or content policy page, subtle message, that you use a little bit help of AI for reasearch and get idea for headlines. Can't say if showing so much kindness will help you because google is not kind to you (to us all) !