Can I Inject a completely different tag property to my site for testing?

I have a site that is segregated with two different tag properties. X(new) Y(old) & both send the data to one report suite. My goal is to update the implementation so that only one tag property is used across the site.

My question is: in my site, where pages contain Y property, can I inject property X to do my tests to see if the rules are firing and variables are being captured? or does the platform debugger only allow different environment of the same property?