Available as an assembled Module and as a DIY project.
This Module is currently available.
Midi Splitter 11 buffered outputs
Tymkrs presents the M2M Module – a fully-assembled and tested 2hp MIDI-splitter or MIDI-thru Eurorack module allowing you to take 1 optoisolated MIDI input (TRS Type A) to output copies to 11 buffered MIDI outputs!
This is easily powered by a standard 8x eurorack power supply on the +5V rails. And any MIDI serial traffic coming into the module will be reflected by an activity light.
You can choose to plug your MIDI input into the top front jack OR the top back jack. The MIDI input is normaled to the back. The input on the back is the default MIDI input unless something is plugged into the MIDI input on the front of the module.
https://www.tindie.com/products/tymkrs/tymkrs-m2m-2hp-midi-thru-eurorack-module/