The supported op name in the converter is “Negative”, the code snippet is using “Neg” so it says it is unsupported. The converter expects the op to be called Negative. It’s possible that the name has change in latest version of TF. You are using Tensorflow 1.10. Unfortunately, TensorRT 4.0 doesn’t support TF 1.10 yet.
For using leaky relu, the user can use provided LReLU plugin.