I soon chat freely, as part of a conspiracy (2,7)
I believe the answer is:
in cahoots
'as part of a conspiracy' is the definition.
(people in in cahoots are conspiring together)
'i soon chat freely' is the wordplay.
'freely' indicates an anagram.
'soon'+'chat'='soonchat'
'soonchat' anagrammed gives 'ncahoots'.
'i'+'ncahoots'='IN CAHOOTS'
(Other definitions for in cahoots that I've seen before include "Working with" , "Colluding" , "Thick" , "Conspiring together" , "what conspirators are" .)