The most common and most likely answer to this crossword clue is the 2 plus 6 letter word IN ACTION
I've seen this crossword clue in Financial Times
I
N
A
C
T
I
O
N
More clues leading to the result IN ACTION
Buddy explains!

The straight part
We know that "Working" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case working = in action.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.