I have posted to this link, reposting here in case it’s useful for someoone
How to make Ghost and Netlify work with /blog (hint: Cloudflare Workers) | by Kan Yilmaz | Medium
I have wrote a hack on how to do it. It’d be great if Netlify allowed reverse proxy functionalities. I don’t necessarily recommend this solution to anyone. It’s a hack to get going without more headaches.