As I said I wouldn't use Swedish language without a Swedish keyboard, even though it's quite possible (just 3 missing characters basically). What I'd do is switch to english language instead.
Hmm, I've never encountered situations when only English keyboard is available for communication (except for when someone is setting up a new Linux machine).
But even if there is such situation, I don't think that would happen, I'm not sure if Swedish is similar to English but English is cognitive load here. Even with people that are proficient in English, I cannot imagine myself communicating with the English language.
I remember myself resorting to online keyboards though(while setting up Linux).