Different, but possibly related (7)
I believe the answer is:
altered
'different' is the definition.
(I've seen this before)
'possibly related' is the wordplay.
'possibly' indicates anagramming the letters.
'related' anagrammed gives 'ALTERED'.
'but' acts as a link.
(Other definitions for altered that I've seen before include "Treadle (anag)" , "Metamorphosed" , "Changed, adapted" , "Reformed" , "Change" .)