Any devices that can emulate multiple HID keyboards? (i.e. multiple USB ports)

I'm trying to build a device with a single ethernet port and multiple USB ports that can emulate multiple HID keyboards.

The goal is to build a TCP/IP to HID keyboard device so I can send TCP/IP commands to the device and then have it translated to a keyboard. Instead of having multiple Arduino Uno (?) + Ethernet Shields, it would be nice to combine everything into a single device and only need a single ethernet connection as well.

Why do you need multiple keyboards?

My crystal ball says that you want a device that acts as a HID on its USB port, and simulates key presses according to received TCP/IP commands.

When you search for a HID implementation on an Arduino, you may end up with a Leonardo or similar board, that allows to configure its USB port accordingly.