It is worth it to change the language of the product URl
This is mostly seen on e-Commerce websites such as Magento-based ones. These are actually the most widely used e-Commerce site. If the store has both German and English translations, the product URL cannot be similar for both German and English. It also pays to translate even the content of the web pages.
Be open to accepting language headers or auto-redirecting based on IP
Google has something to say when it comes to redirecting users automatically to the version of a webpage in a different language: one should avoid being redirected automatically, because it could lead to other users not being able to view all the versions of the website.
It might be weird because Google doesn’t really follow what it says – it still redirects automatically even if you visit a website from another country. If you decide not to follow what Google says, Google added something to the rel alternate which you may need to let Google know what your default language is: x-default hreflang. Yandex, the hugest search engine in Russia, also lets users do this.
Mixing rel canonical and rel alternate should not be done
If your rel alternate is properly done, you might wanna double-check rel canonical, because you might also want to do some revisions. Do not employ canonical to direct different versions of your website to your main language. A bad example of this would be something like “website.nl/content-in-dutch.html canonical points to website.nl/product-name-in-english.html.” Instead, you may opt to do this: “website.nl/content-in-dutch.html canonical points to website.nl/content-in-dutch.html.”
Not allowing translated web pages or non-indexing through robots.txt does not help
Google says you don’t really need to hide the other versions of your website through disabling crawling throughrobots.txt or using a robots meta tag such as “noindex.” This would especially be detrimental if you did not carry rel alternate out properly. Even if you have other tricks done, it is not necessary to hide the duplicates.
Cross-linking done improperly or not cross-linking at all does not help either
You should use internal hyperlinks for linked translated web pages. That way, search engines and other users will be able to access it. People usually use country flags to represent it, or they use a text link with the language. If you want to truly optimize, you should not link all the web pages translated in one language to the home pages of different languages. Instead, you should use the best version of the URL. This is what you should not do: “website.com/content-in-english.html links to website.nl.” Instead, you should do: “website.com/content-in-english.html links to website.nl/content-in-dutch.html.”
Multilingual SEO is not simple to do and having an expert on it could save you from a lot of stress with trial and error. If you want to translate your website to other languages it is always best to have a specialist working on your multilingual SEO.