Automated ships that will go to destination, load a train with naq (or whatever you set), then return and unload said train. A single ship doesn't do much but the idea is to get around a dozen or so pasted down.
Can be improved, but this is what works for me.
Mods used: Space exploration, Space trains, text plates, repair tower, Krastorio 2.
SE and Krastorio 2 are the only real 'required mods' and K2 can be edited out.