Currently the plugin is able to add the multilingual urls to the sitemap, and you need to add the following line at the sitemap-core.php, add-url function (line 1509 at version 3.2.2 right after the AddElement)
Plugin sasa ni uwezo wa kuongeza URL ya lugha ya Ramani ya, na haja ya kuongeza line zifuatazo saa core.php ya Sitemap-, add-url kazi (line 1509 saa version 3.2.2 haki baada ya AddElement)