The Generic Remote doesn’t have Learn function for the parameter assignment. This Learn function is to learn the MIDI Message you want to assign.
It might happen, the parameter is missing. For the tracks mostly the automatable parameters are available. If the parameter is not automatable, there is quite high probability, you cannot find it in the list.
Even in case you would find it, be aware, the parameter is linked to the specific fader slot, not to the channel. So once you would change the tracks order, it would stop to work.
I’m afraid there is no way to do what you are requesting. Sorry.