Translation:The Chinese workers go out onto the street.
"Onto the street" seems fine to me. One of the images it evokes is a pedestrian stepping from the sidewalk onto the pavement - the main part of the street.
To the street - unless when you give directions you may say "turn on to Broadway" because you expect them to stay on it longer. Otherwise "onto" in one word is not used.
"Turn on to Broadway" sounds wrong to me. Perhaps different English usages?
On the other hand "turn right on to" (with quotes) in Google suggests "did you mean "turn right onto"?), and that version has lots more search results.
Google also finds lots of hits for "he went out onto the street" (with quotes), including results from books (i.e. edited prose, hopefully).
I think your English Sprachgefühl is not consistent with the majority of speakers in this point.
Well, I've only lived in the States for 25 years and spoke English since 5th grade... but what do I know. The directions things is true, that's what they say in the UK and here in the US too. What do you guys think? People who didn't learn English online?
As it's both 1. not a difference you'd actually hear when spoken, and 2. not something you typically see written (street directions are usually verbal only, if not directed by a GPS), it's a minor grammatical quirk that I don't know, but don't care about or indeed notice either.
The only differences I can glean from a Google search - which I must resort to, because despite English being my native language, this is such an infinitesimally insignificant point that no one bothered to teach me - are that 1. on to is more standard in the UK and other Commonwealth countries, whereas onto is more standard in the US, and 2. it should always be on to if "on" is a part of the verb itself, as in let's go on to the next point (example sentence from this page), where "on" is part of the verb "to move on".
That said, can we now move on to more important matters?