Domain mask for subfolders and different sites

Hey @juan.colomer,
I will get straight to the point.
There are several ways to achieve that, and you will do that within your server set up.
Cloudflare will follow any redirects you will call to (within your server’s or app code)
That depends the server that you’re using (Apache, ISS, etc) and use the right redirects on your code.
You can follow the topic right over here, which more or less seems to be very similar to yours.

Cloudflare workers → You can check the GeoIP redirection worker - #7 by user8105

However, (my personal opinion on this matter), I wouldn’t suggest an automated redirect users based on their location, unless of course this is something that has to do with the law.
In that case, you can use your main domain for the main language and redirect users to the other site with a simple button on the header that will tell the users “US site or anything else” and get them to the sub-folder-ed site.

Let us find more about what you want to achieve and we will be able to help more.