Translation:Excuse me, where can we exchange money?
It's not Chinglish at all.
"Change money" has a long history in English (as does "money changer(s)"), and it's not much of a stretch from that to "exchange money". "Exchange currency" is fine too, but "exchange money" is also common and there's lots of evidence of its use in mainstream publications and other native-sounding text on the internet.
Encyclopedia and dictionary references
Collins has the following example/explanation:
"When you change money, you exchange it for the same amount of money in a different currency, or in smaller notes, bills, or coins.
That hits both "change money" and "exchange it".
How to Change Money to a Foreign Currency
US Travel Insurance Association
How To Exchange Money In a Foreign Country
Google Ngram Viewer
The following Google Ngram Viewer search isn't determinative (there are certain to be phrasal effects not captured by its parameters), but it has "exchange money" above "exchange currency" in English-language books (and shows "change money" as more common than both):
You can't use Google Ngram Viewer in that way as supporting evidence. "Change money" on its own without any context has many meanings and uses outside of currency exchange. Google is counting every occurrence of "change money" it finds. Showing its prevalence in comparison to exchange money and exchange currency without any context is either misguided or dishonest.
Consider the following sentences:
"Banks can change money market rates at any time."
"They have decided not to change money order prices next year."
I just had to! As the sentence contained 我们, I wrote "Excuse US..." and was promptly tarred and feathered into a fine 5 foot 8 green duster. Gotta be a glutton for punishment to came back here, day after day, yes? ;-p