You might want to indicate whether you are asking about BE or AE. If I understand the question correctly, for AE, rule 7.89 in the Chicago Manual of Style, 15th ed. is applicable (sort of):
»Hyphen with word space. When the second part of a hypenated expression is omitted, the hyphen is retained, followed by a word space.
fifteen- and twenty-year mortgages
Chicago- or Milwaukee-bound passengers
I haven't found anything specific to comma-separated lists yet, but it seems to follow by natural extension from the above that one would write
English-, German-, and Chinese-speaking staff.
I am not a language maven, so you might want to stick around for a second (or even third) opinion.