[@Afro Samurai]  Belasy and Izkry were born German, but their father ensured they escaped to Switzerland.  They are Swiss citizens and have served a few years in the Swiss army.  Both are fluent in German (also known as German Standard German), Swiss Standard German (similar but not quite the same), and Swiss German (despite its name, actually very different, and consisting of many different local dialects).

It turns out Switzerland actually has a number of official languages, which is why the pair know certain other ones as well.  Bel in particular is good with languages (the irony).  If Belasy talks Walter will likely be able to understand her.  Her accent is not that strong -- lightly Germanic, more British than anything else.

Good luck getting her to talk.

But yeah, Izkry has mentioned coming from German offhand perhaps, but he's always called himself Swiss if nationality came up, and since Walter has not been around long, I don't know if he'd know any of that, nor even what language Izkry was speaking for the handful of words.