How to hide from the site owner the source of the link to his site?

Question

PHP

There is a site site.ru and its subdomain sub.site.ru.
The subdomain sub.site.ru contains a link to a third-party resource resurs.ru.
How to make it so that the owner of the resurs.ru resource in web analytics would see the source of the transition to his site site.ru (and not sub.site.ru), despite the fact that the link is located on the subdomain sub.site.ru.
Possible solutions:
1. We make a link to sub.site.ru not like this:

<а href='http://resurs.ru'>Ссылка на сторонний ресурс< /а>,

and like this:

<а href='http://site.ru/link1'>Ссылка на сторонний ресурс< /а>

and set up site/link1 → resurs.ru redirect to site.ru in htaccess
2. Some php script on the sub.site.ru page, which tells external links that the source of the transition is not sub.site.ru, but site. Common crawl en
There are online services for hiding the referrer such as href.li, url.rw, hidereferrer.com.
How to implement such functionality, but on your own?
Why you need it: on the subdomain there is an analytics of the price lists of companies with links to their official websites where these price lists are located. It is necessary that companies do not see that on sub.site.ru their price lists are compared with competitors and analyzed. Although they themselves provide them in open access. On site.ru general information on the market.
Tell me how to implement this, maybe there is a ready-made solution for your own site, not a third-party service?