Virtues displayed by monarch in swirling mist (6)
I believe the answer is:
merits
'virtues' is the definition.
('merit' can be a synonym of 'virtue')
'monarch in swirling mist' is the wordplay.
'monarch' becomes 'ER' (abbreviation for Elizabeth Regina, British Queen).
'in' means one lot of letters goes inside another.
'swirling' indicates anagramming the letters.
'mist' anagrammed gives 'mits'.
'er' placed into 'mits' is 'MERITS'.
'displayed by' is the link.
(Other definitions for merits that I've seen before include "Deserves to be praised" , "Virtues of timers" , "Deserves, is worthy of" , "Legally right or wrong" , "Deserves or warrants" .)