The most common and most likely answer to this crossword clue is the 7 letter word PAUPERS
I've seen this crossword clue in Independent
P
A
U
P
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R
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More clues leading to the result PAUPERS
Buddy explains!

The straight part
We know that "Souls essentially dressed in rags? (7)/Souls essentially dressed in rags?" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case souls essentially dressed in rags? (7)/souls essentially dressed in rags? = paupers.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 PAUPERS mean?
PAUPERS noun- One who is extremely poor.
- One living on or eligible for public charity.