The most common and most likely answer to this crossword clue is the 6 letter word PROUST
I've seen this crossword clue in The Guardian
P
R
O
U
S
T
More clues leading to the result PROUST
- Pair to remove and replace French writer
- French author in drunken stupor
- Heartless publisher to get rid of French author
- Spin doctors inaccurate about Society writer
- French writer advocating American accent in the end
- Novelist in drunken stupor
- Writer in favour of American technique, initially
- Head of Penguin right to sack author
- Origins of Remembrances of Things Past, unfinished script edited by…?
- Novelist’s page put out about opening of ‘Remembrance…’
Buddy explains!

The straight part
We know that "French author" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case french author = proust.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.