Blackmails using rearranged letters, or texts (7)
I believe the answer is:
extorts
'blackmails' is the definition.
'using rearranged letters or texts' is the wordplay.
'using rearranged letters' indicates anagramming the letters.
'or'+'texts'='ortexts'
'ortexts' with letters rearranged gives 'EXTORTS'.
(Other definitions for extorts that I've seen before include "Obtains money with menaces" , "Gains by threats" , "Threatens for money" , "Obtains by force or intimidation" , "Obtains by coercion" .)