Wonder Woman is a harder opponent than either Captain Atom or Martian Manhunter for Thor imo. WW is tougher because she has speed, the Aegis is a great defence, has no major weaknesses and she's very tactical. CA weakness to being punctured and drained might just be as bad as John's weakness to fire. Which are really really bad weaknesses when facing Mjolnir.
He stops at her. If he fights smart and saves his energy (Heat against AM and Namor, lighting against Hercules etc.), he'd get to BRB.