Karpova: According to 'Wiener Schachzeitung', September-October 1905, p. 310 this game was played in the Jubilee tournament (75th anniversary) of the Hamburg Chess Club (May 1905), and Black was <Dr. Schwarz>.
A player of that name did not participate in the tournament, and the 'Wiener Schachzeitung' doesn't claim that either in their tournament report (July-August 1905, pp. 248-249), giving instead <Dr. Sohège>.
Rod Edwards has <Max Sohège> participate in the tournament: http://www.edochess.ca/tournaments/....
So either this game is not from the Jubilee tournament, or Black was probably Max Sohège and not Dr. Schwarz (Leonhardt beat Fahrni, von Bardeleben, Bier and Sohège. I know the games against Fahrni and von Bardeleben, so only Bier and Sohège left. I doubt that Bier's name was confused with <Schwarz> though, and the <Dr.> in front of both, Schwarz and Sohège, is another indicator).