Usually, if you want to work in international schools worldwide, you need to have a teaching degree from one of the English-speaking countries (AU, US, CA, UK, ZA, NZ), and usually you would need to do at least some, if not all, of the practical teaching work within the country. (Note also, that the decent schools mostly require you to have 2 years experience teaching post-graduation.)
Whether Swiss international schools require the same, I do not know, but generally the English-speaking ones are going to follow a US or UK curriculum, so I imagine it would be an advantage to have a degree from there.
As mentioned above, some Australian universities offer a Grad Dip in Education by distance, but you'd still have to do some or all of the teaching in Australia. That might work out to something like 30 days teaching in Oz and 30 days elsewhere, in Switzerland for example. (Check out Monash, UNE, CSU, USQ, Murdoch and Deakin.) Perhaps the UK has something similar.
I don't think there would be any education studies in English in Switzerland though. I could be wrong. There is a course for young learners in Germany, but it doesn't lead to a formal teaching qualification. There is nothing on this list...
http://www.crus.ch/information-progr...glish.html?L=2
Good luck!