I assume that in your case WordPress is used as a Content Management System so only authorised users can log in rather than members of the public.
If you have granted a user an Admin or Editor permission then he/she are not going to scrape the site.
You can then exclude the
/wp-admin/
from WebScraping policy.
Unauthorised users and scrapers will only hit the login screen when trying to get any URL under /wp-admin/ and won't be able to log into the WordPress Admin so nothing to scrape there apart from the login form.
The scrapers will be after your public content which will be on the main website URLs and /wp-content/ path.
Generally speaking any CMS system is a headache for ASM Administrators as it requires very careful and precise policy tuning.