Could you please clarify what you mean by “Orin Nano does not support DeepStream 9.1”?
The current NVIDIA DeepStream 9.1 documentation clearly mentions support for Jetson Orin (Nano, NX, AGX) and states that the Jetson package is based on JetPack 7.2 GA (r39.2 BSP).
Also, the original libgstnvdsseimeta.so.1.0.0 / nvstreammux issue is resolved by installing nvidia-l4t-gstreamer (39.2.0-20260601141651), and DeepStream 9.1 is now working correctly on the Orin Nano.
Sorry, this appears to be an issue with the DeepStream documentation; the compatibility table I mentioned earlier indicates that JP-7.2 does not support the Orin Nano.
This link suggests that the Orin Nano does support JP-7.2. And the link you provided also confirms this.
If the method above solves your problem, I will look into the documentation.