New site redesign

I will redesign a existent website

What is the better option?

1. create a site with domain hml in Cyber Panel an then after the development, change its domain to definitive
2. create a site with definitive domain an then create a staging subdomain to develop the site
3. create two sites, one with definitive domain and another with hml domain and after development, copy the content between sites.

The existing site is a WordPress site, is the replacement also being built in WP?

If it is then I would suggest developing it in a subdomain or separate domain and then using a backup/migration plugin (I like WPVivid) to migrate everything from the new version to the old one.

Thank you very much.
The original site is empty, but I wont point DNS to it, because there is a actual site in another server.
So I will create a sub domain and make a new site.
I use All In One WP Migration, because I have a perpetual license.

Thank you for the help.