Since I'm from South Africa (a former British colony) and attended a British school, I mostly write English in a British way. Given that there are also Americans in Switzerland, one also comes across American spellings in written text. This had me wonder which version of English would be "most standard" for use in Switzerland.
The country only has four official languages (German, French, Italian and Romansh) so English, as usual, is not prescriptively standardised. It means we need to select an appropriate sample of people and go for a more descriptive answer. Maybe what's most relevant is what kind of English spelling is taught in Swiss schools? Do Swiss schools tend to use textbooks from the UK or from the US? If a Swiss person were to read the Bible in English, which translation would they be most likely to choose?