Solved by seungjun in post #4 
              
              
                I recently read about ONNX runtime and it might be an alternative. 
PyTorch could export models to ONNX format and run the model with ONNX runtime. 
https://pytorch.org/docs/stable/onnx.html 
According to the onnxruntime, NNAPI is supported including CPU and GPU inference. 
I didn’t try it but looks…