Lying agent overseas in German capital (8)
I believe the answer is:
reposing
'lying' is the definition.
(reposing is a kind of lying)
'agent overseas in german capital' is the wordplay.
'agent' becomes 'rep' (short for representative).
'overseas' becomes 'os' (abbreviation).
'capital' indicates taking the first letters.
The first letter of 'german' is 'g'.
'rep'+'os'+'in'+'g'='REPOSING'
(Other definitions for reposing that I've seen before include "relaxing?" , "Smiling again for the photographer" , "lying" .)