It worked. I downloaded patch 2.20.21 as an experiment. Each team has its own spawn area on a new planet. Unfortunately, you have to restart the save game and cannot use a save game from the previous patch. Thanks anyway. It worked.

thank you very much for wanting to change that.
Yes, we always played without walls and towers.
When the patch is out I will definitely try it out and give feedback

Dear Factorio team,

first at all, i want to tell you all how i like this game. Space age is a nice thing and it makes a lot of fun.

But now, i have to ask you something,
i have made a multiplayer map with my friends as a PvP scenario. We don't play against each other, but we play on the same map ...