I thought i’d explained there wouldn’t be, you want to merge two physical ports, it can’t happen internally . .all the hardware solutions are documented in older threads
It is very rare for devices to serve up a virtual merge in the manner you’d like and it most certainly isn’t part of the MIDI spec
You need the OUT stream and the THRU stream , so you’ll need to merge these on a device, the other threads will spoil you with suggestions
My favourite tool, and also potentially the cheapest solution is a 8x8 s/h device
like so