Mavlink stream to arduino from GS

Hi, I’m building an antenna tracker, not using the classical AT software.
My goal is to use an Arduino/teensy with 2 stepper motors linked to the pc via usb, and the antenna for telemetry also linked to the pc via usb, i need to stream the mavlink data received to the pc at the arduino as is, so i can use the arduino library to read data from the gps.
With the actual position of the drone, i can move the antenna accordingly.
What software i can use to do this type of relay?
I’ve make a simple diagram to explain better my setup.
Thanks for any suggestion