In a sombre pose, disturbed, but rested (7)
I believe the answer is:
reposed
'rested' is the definition.
('repose' can be a synonym of 'rest')
'in a sombre pose disturbed' is the wordplay.
'in' says the answer is hidden in the clue.
'REPOSED' can be found hidden inside 'sombre pose disturbed'.
'but' acts as a link.
(Other definitions for reposed that I've seen before include "Relaxed" , "What's settled" , "Rested" , "modelled afresh" .)