Audio routing for stereo export

Hello everyone.

I usually work with xdcam mxf 8ch: I need to export in mp4 with channels 3-4 of the mxf as a stereo audio for mp4.

In premiere is easy but a bit complex. When I try to do it in AME (it would be perfect for me using watchfolders), the mp4 has the first 2 channels of the mxf.

Episode from Telestream was my first choice, but now it's discontinued. Is there a way to do it in AME?

Thanks in advance!