We put coastal markers from HBG under them.
But the simplest way to get “rid of” the coastal ships, is just to make them like their regular counterpart. And remove the whole coastal concept from the game.
China does not lose it’s IPC’s when Szechwan falls.
Neutrals that are attacked become “Pro” for the opposite side, and must be activated in order to move and attack with the activating powers forces/turn.
Note that activation is 1 turn, and you can’t move or attack with those pieces until the following turn.
ROUGHLY - Germany attacks turkey. UK Activates turkish capital. Germany goes again. Uk can now use turkish forces that were activated.