Adds massive cargo ships to the game, that function similarly to trains. Also adds tanker ships, train bridges. NOTE: In 2.1, You Must Install Oil Rigs Separately!
So how about adding a different type of port that ships can automatically head to when they are low on fuel? Similar to magu5026's "Automatic Train Fuel Stop" https://mods.factorio.com/mod/FuelTrainStop
That feature could be added to that mod, similar to how LTN makes LTN Ports when it sees Cargo Ships is installed. I do not think we will add it to the Cargo Ships mod.