Hell even the delivery along routes issue is one that can and has been solved in the past. The railway post office sorted mail en route for by postal clerks and existed as late as the 1970s, because Nixon was from SoCal and we really like our trains. While it may not be fully applicable it could still work for smaller liquid sort items, as for larger carriage specific ones I’m aware of at least one railyard that used to have those ones unlatched and moved as needed within a 5 minute period not accounting for stopping.