Some short updates:

1. The Matrix PCBs arrived. I will post some Images here, when I soldered one.

2.The Layout for the Main PCB is ready! I ended with a pin header to use ESP-01 Modules for the connectivity. Here some nice renderings:

The front LED side with five LED PCBs. Here in red

The Pack with all the LED control Stuff, an STM8 Microcontroller and a pin header to add wifi with an ESP-01:

Like This it should look with an ESP-01: