This game is also available in the GooglePlayStore as "Moorhuhn Kart Multiplayer Racing".

https://play.google.com/store/apps/details?id=com.GeekPit.Kart

As it is the same game, just for Android: Is this version also allowed here, or only the Steam-Version?

The mobile version appears to be the same version of the game, but it would be a different category. I'll add it to the leaderboard

Thanks!