Author Meta in Author URL Link

This is just an example / idea and I haven’t tested if this really works. But I think it could be something along these lines.

function custom_author_base() {
    global $wp_rewrite;
    global $wp_query;
    // On author pages you get current author for example with $wp_query
    $curauth = $wp_query->get_queried_object();
    // Get the required data
    $country = get_user_meta($curauth->ID, 'country_meta_key', true);
    // Turn the country into url friendly format and prepend it to operator
    $author_slug = sanitize_title($country) . '/operator';
    // Set the custom string as author base
    $wp_rewrite->author_base = $author_slug;
}
add_action('init', 'custom_author_base');

This example will propably need some tweaking. You might also need extra functions to handle other cases than the auhtor page where the author page url is shown. E.g. get_author_posts_url might need some tweaking I guess.

I hope this helps you achieve the result you’re looking for. Or perhaps others can build on this and help you find a more complete solution.