I noticed that wherever on the site a user's profile is linked, its linked without the language code in the url.

Like, lets say i see everywhere this public profile:
https://www.kalosex.com/user/profile/John250

But the best would be to include the language code (en for english or gr for greek):
https://www.kalosex.com/en/user/profile/John250

No matter if you change language, the profile url remains the same and doesn't include lang code. So, considering that based on the lang used, the content of page changes but the url remains the same, it's a problem for SEO. Especially while everywhere on the site the lang code is on the url.

So i wonder, how can i edit the links to profiles on the theme so it includes the url code that the users is using currently?

Is there a way to do this so i don't get indexed urls without lang code?

I see that the link is produced with this code "<?php echo eps_user_public_profile_url(osc_item_user_id()); ?>" so i guess it's more of osclass thing and not theme's, so maybe topic needs to be moved to correct spot of forum. Sorry for this

Can you try with osclass function instead?
osc_user_public_profile_url(osc_item_user_id());

Just tried, it produces same link

Hmm not sure why just this one woukd not work.
Will try to test tomorrow...

OK there is bug, in helpers/hUsers.php
find:
        $path = osc_base_url().osc_get_preference('rewrite_user_profile')."/".$user['s_username'];

Replace with:
$path = osc_base_url(false, true) . osc_get_preference('rewrite_user_profile') . '/' . $user['s_username'];

the change on helpers/hUsers.php and the osc_user_public_profile_url(osc_item_user_id());
did the trick. Thank you