1. Suppose yes.
Our uff converter takes frozen .pb file as input.
So please convert your tflite model into .pb format first.
Here is a related information for your reference:
After that, you can follow our sample to convert .pb -> uff -> TensorRT engine.
2. AFAIK, there are some issue to load tflite model with TF-TRT.
We recommend to use pure TensorRT since it will give you a better performance.