Can a government or central bank work to reduce inflation without hiking interest rates and causing the currency to appreciate?
Yes, but only if you also introduce capital controls. You should check out the Mundell–Fleming trilemma:


  The Impossible trinity (also known as the Trilemma) is a trilemma in
  international economics which states that it is impossible to have all
  three of the following at the same time:
  
  
  A fixed foreign exchange rate
  Free capital movement (absence of capital controls)
  An independent monetary policy
  


Wikipedia Impossible Trinity