Google Search Console – Adding Domain/Subdomain and sitemap for each

I have a WP website http://testexample.com and created a new subdomain with separate content and URL http://subdomain.testexample.com and I need to register both sites in Google Search Console now. The idea is that both sites are visible on Google and to be SEO optimized for different content they have. What is the best way to do this:

1) Add a new property type (Domain) of a testexample.com (without http and www) and after that just to submit both sitemaps (http://testexample.com/sitemap.xml and http://subdomain.testexample.com/sitemap.xml)

2) Add a new property type (URL Prefix) for both sites (http://testexample.com and http://subdomain.testexample.com) and a separate XML file for both sites in the correct property where they belong.

3) Or some other way?

Regards