Feature request: Ability to rewrite full URL or subdomain

I started to use the Transform Rule functionality as I wanted to rewrite where:

(http.host eq “www.experteasy.com” and http.request.uri.path contains “/blog/”)

To:

concat(“https://blog.experteasy.com.au”,http.request.uri.path)

But that I realised the field I was entering is only for http.request.uri.path rather than full URL and it will not work.

My ‘main site’ and ‘blog’ are hosted on different IPs and the rewrite currently happens on the ‘main site’, enabling ability to rewrite full URL or subdomain would give a better TTFB for many users with similar setups.

That would require the ability to rewrite Host Headers, which Cloudflare does not permit for security reasons unless you’re on an Enterprise plan.

If it was limited to the ability to rewrite only to a subdomain on the same root domain would it still be a security concern?..and if so why?

Is anyone else able to answer the above?