Who Streams Karakai Jouzu No Takagi-San Season 1?

I have no idea where to watch Season 1 …

With Netflix there's unfortunately only the second season

Legal at Crunchyroll with subtitles.
https://www.crunchyroll.com/...takagi-san

And illegal? : 3

Why do you want to watch it illegally when you can just as easily and legally watch it?

However, if you are interested in a German synchro, the season was not dubbed as far as I know.

Legal, as far as I know, only possible with crunchyroll with gersub. : 3

Yes, I'm about a German, well a shame, thanks anyway

I guess the anime (season 1) is probably nowhere in German dubbed. That's why you'll likely need to use Crunchyroll. The second season on Netflix also says that it is a Netflix series. This is probably because it only runs on Netflix with German Synchro.