Mimic cuts credit for illegal scheme (5)
I believe the answer is:
caper
'illegal scheme' is the definition.
(I've seen this before)
'mimic cuts credit' is the wordplay.
'mimic' becomes 'ape' (I've seen this in another clue).
'cuts' is an insertion indicator (some letters cut their way into other letters).
'credit' becomes 'cr' (abbreviation).
'ape' inserted within 'cr' is 'CAPER'.
'for' acts as a link.
(Other definitions for caper that I've seen before include "Jump about playfully" , "One likely to get pickled" , "Frisk" , "Frolic - bud used in cooking" , "Skip about for the sauce" .)