Havent seen it metioned yet… but whether or not the hub or gear is being driven or free depends on the design of the transmission. For example, in a W5MG1 (3000GT VR4 Transmission) the main shaft drives gear sets 1, 2, 5 and R, while hub & slider 3/4 are also driven on the main shaft. In this example, 4 gears are and 1 hub/slider is driven, not all gears or all hubs.
Also, I have gear sets, main/counter shafts, hubs, sliders, single and double cone synchros laying around… if anyone wants pictures of something specific, let me know.