Passenger trolleys rarely pulled freight cars; passenger trailers were pulled.
All sorts of freight motors of very diverse designs pulled freight cars of both routine freight car styles as well as rather specialized cars.
For a good overview see:
Not Only Passengers: How the Electric Railways Carried Freight, Express, and Baggage (CERA Bulletin 129) Hardcover – January 1, 1992
by Roy G. Benedict (Author), James R. McFarlane (Author)