Let's say I have a website that has 2 languages, one uses Latin and the second one Cyrillic transcriptions in URLs.
For example:
My question is which is more user and SEO friendly, if I leave them as is or if I add the language prefix, so they'd become
I understand that such subdirectories should be used if I have languages that are similar and then the user wouldn't be confused, but does that also apply in my case?
It's better to use the second one for better SEO results.
example.com/en/link
example.com/ru/ссылка
Google likes the tree-like structure. Of course you can use the main language without prefix.
Also it's better to have all languages in one domain:
domain.com/en
domain.com/ru
not on subdomains like this
en.domain.com
ru.domain.com
Wish you luck.