Not sure what the official stance is, but people with Turkish names seem to (often?) transliterate ü = u, ö => o, as seen for example at https://twitter.com/mes

Not sure what the official stance is, but people with Turkish names seem to (often?) transliterate ü = u, ö => o, as seen for example at https://twitter.com/mesutozil1088 https://twitter.com/mesutozil1088 and https://twitter.com/ismail_kupeli https://twitter.com/ismail_kupeli - not sure about Swedes.