Tool to export pytorch model as onnx graph, based on torch.onnx.
python exporter.py -m model.pt -o output/model.onnx
python exporter.py -m detection.maskrcnn_resnet50_fpn
python exporter.py --hub-repo ultralytics/yolov5 -m yolov5s
Any onnx visualization tools are ok, I recommand Netron: