I don't think X as "sh" in Spanish exists (but I could be wrong). But Mandarin as transcribed in pinyin has it. Also in English x is pronounced as z at the be

I don't think X as "sh" in Spanish exists (but I could be wrong). But Mandarin as transcribed in pinyin has it. Also in English x is pronounced as z at the beginning of some Greek-derived words like Xerox and xylophone.