No, apparently Swiss German is not included in the language recognition list.

Yes, I have already recorded several sessions in which dialect was spoken. But they were Zurich, Aargau and similar ;-) reasonable dialects. I can't (yet) confirm whether it also works with Valais, Bernese, etc. :-)

I don't know, I've only used it in French so far 🤔

That's called recognition of the German language, but your question has now prompted me. I tested with the beginning of the Tschuger series (S1-ep1) and here is the result.

Speaker 1 00:00:11
The flapping of a butterfly's wings on the other side of the world can read the storm. This story is about a butterfly. But I didn't even get to the flapping of the wings. But first I have to tell you briefly how much dubbel I have to deal with every day.
Speaker 1 00:00:47
This one here, the junior, likes to smoke one while working. And later he'll say that he wants to get a prescription from Dr Burgen. That's when you go into a high. Oh shit. Everyone knows that he just likes to play one to. But when it comes to handling heavy machinery, this stuff really isn't recommended

J'espère que ça peut aider.