Many international congregations ask local congregations for rooms for their congregational life. But it is difficult to find rooms in big cities.
The representatives of the regional churches would like to offer assistance in this matter. They are pastors responsible for supporting fellowship between international und local congregations.
You can also talk to them if you wish to contact other congregations in your vicinity. That is their job, especially if you want to have your congregation recognized by local authorities (“eingetragener Verein“ = recognized association) or wish to purchase a church building.
You will find the responsible pastor in your region here
You could also ask other Evangelical, Roman Catholic or Orthodox Churches as well as at the local ACK if they could provide you with rooms.