In Europe, it is in many countries the short form of fashist.
In
Germany, for instance, "ein Fascho" translates to "a fashist", or "
das ist aber fascho" (eng. "that is so fashist"). Even Google Translator translated "Er ist ein Fascho" into "He is a
fascist", and equivalent to "fascho" (adjective).
It is, however, not related to the American Black slang of "fasho" as "for sure".