For what it's worth, I understand that Trix, in both England and Germany, sold locos in the late 1930s, i.e. 70 years ago, with remote uncoupling. This depended on the AC reversing mechanism as the Trix OO/HO offerings at the time were all AC not DC powered. The remote uncoupling system was lost when Trix in England later switched to the Peco/Hornby Dublo style coupling. Trix moved over to DC in the mid-1950s anyway.