No Neutrality
I would expect that, if Switzerland has a seaport before the Great War, Neutrality would have been impossible--they would have been drawn into The Great War or World War II. A seaport is too valuable to leave unmollested. If one side controls the sea, and the other has borders on Switzerland, there's a fine chance to turn that sea command into a beach head, either by diplomacy or surprise attack. Both sides in the Great War were quite heedless of the rights of neutrals...
If there's an adequate Swiss fleet to insure said neutrality, don't forget Copenhagen or Pearl Harbor.
They were able to stay neutral, IMHO, largely because the value of the place wasn't worth the price of invasion.
(I suspect that even a victorious Third Reich would likely not bother, but simply bring the place under its economic dominion, at least for some time. Perhaps dismemberiong the place, to bring all Germans under German rule.)