Different separator and character case settings for different languages

Solved the problem with hook_variable_info.

Added the following code to mymodule.module:

/**
* Implements hook_variable_info().
*/
function mymodule_variable_info($options) {
$variables['pathauto_separator'] = array(
'title' => t('Pathauto Separator'),
);

$variables['pathauto_case'] = array(
'title' => t('Pathauto Case'),
);

return $variables;
}

/**
* Implements hook_variable_info_alter() to make these variables 'localizable' .
*/
function mymodule_variable_info_alter(&$variables, $options) {
// Make the above variables translatable
$variables['pathauto_separator']['localize'] = TRUE;
$variables['pathauto_case']['localize'] = TRUE;
}

Then flushed cache and enabled the variables Pathauto Separator and Pathauto Case at Multilingual Variables /admin/config/regional/i18n/variable. Now one can set up different Separator and Case settings per language.