Cyrillic Url Won't Indexing By Google.

Hi, i have made some correction in the core to make url's on cyrillic.The version of the store is 2.1.1 In fn.catalog on 2839 line I modify it to $str = preg_replace("/[*]/", '', $str); // URL can contain latin letters, numbers, dashes and points only. Everything is working perfect, but google wont index my urls on cyrillic. With this tool Google core web vitals - Full Service Internet Marketing Company & Internet Marketing Tools i see is returning 404 error and can't get title,description and text information on my page. What must be the problem?