Former doorman is overseas trader (8)
I believe the answer is:
exporter
'overseas trader' is the definition.
(I've seen this before)
'former doorman' is the wordplay.
'former' becomes 'ex'.
'doorman' becomes 'porter' (synonyms).
'ex'+'porter'='EXPORTER'
'is' is the link.
(Other definitions for exporter that I've seen before include "one selling overseas" , "One selling abroad" , "Overseas trader" , "One sending goods abroad" , "trading abroad" .)