Pinterest is using the subdomain method of internationalization.
Let's take a look:
tr.example.com
<-- Subdomain Method
- Despite Google saying that they rank subdomains more or less the same as subdirectories/folders, SEOs still debate it.
- Strong opinions on this likely come from success after implementing it, which most likely has nothing to do with the method itself, but rather how it's implemented and the unique site it's being implemented on.
- Subdomains are considered standalone sites and distinct from the main (root) domain.
- A subdomain enjoys the benefits from being part of the same site in terms of reputation, crawl rate, spam score, and tens of if not a hundred other ranking factors. The same site started on a new domain would take much longer optimize in search engines.
- In my experience I like this method because for example if the main site is in the US, you can put the Turkish site on a totally separate site on a server with a local/regional IP.
- Many find
tr.example.com
more aesthetically pleasing than example.com/tr-TR/
(that might not be the proper country/lang code).
I will say that generally speaking it's not typical (or necessary) for a site to implement this if it already exists in that country.
For example, for my site I wouldn't use us.mysite.com since I'm already in the US. However, if I wanted to grow my presence to Turkey I'd create tr.mysite.com.
That doesn't mean you can't do it though. You did state that it's very normal in Turkey, so by all means go for it! Just 301 redirect your example.com
to tr.example.com
.
The method still requires hreflang
annotations and canonicals to be set properly (You may know this, mentioning for those who do not). I wrote an answer about implementing canonicals and hreflangs that might be useful if you decide to implement this.
Make sure everything is sorted with search console and that your sitemaps and etc are updated accordingly!