Phonetic transliteration:
克 (kè) for 'K-',
罗 (luó) for '-roo-' or '-ro-',
斯 (sī) for the final '-s'. In Chinese football media, simply saying
克罗斯 is enough — Toni Kroos has been so dominant a figure since the 2010s that the surname alone is unambiguous in most football contexts.