I would like to localize content on a few of my landing pages by making some slight changes to the dynamic content that I show (the website is a marketplace website and the products are very dependent on language, so I'd like to change the "recommended products" based on the user's language preference, which I'll be getting from the accept-language header).
I will not be translating these pages nor changing their layout. Like I said, I'm only changing some of the recommendations.
If I don't give each localized landing page its own URL, search engines may rank and reference content that may not actually be shown when the user clicks through to the site. This would obviously be bad for SEO. This is why most references (example) recommend that localized pages have unique URLs.
On the other hand, it seems like overkill to give each language its own URL, especially if I'm not planning on translating these pages. Moreover, it might even be misleading to have a URL like
example.com/ru and serve content in English.
What is the recommended approach if I'd like to tailor the "recommendations" section by user language preference?