Not a direct answer to your question. But few days back I saw a video on Backlinko which I don't remember now but Brian Dean (founder of Backlinko) said write cold emails with some readymade format that he gave. So my advice is you watch his videos because all he talks about is SEO so that might help. Also, he gives some tips on how to contact all the website owners via Email with the same readymade format. I have only watched 3 of his videos but they were full content and very helpful. So maybe ask him too because he answers most of the questions on his youtube channel.