The most common and most likely answer to this crossword clue is the 10 letter word BUSYBODIES
I've seen this crossword clue in The Daily Telegraph
B
U
S
Y
B
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More clues leading to the result BUSYBODIES
Buddy explains!

The straight part
We know that "‘Snoopy’ characters" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ‘snoopy’ characters = busybodies.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.
What does BUSYBODIES mean?
BUSYBODIES noun- Someone who interferes with others; one who is nosy, intrusive or meddlesome.