Is it possible to convert OpenSeq2Seq Jasper into trt engine file?

I have freeze pb file with OpenSeq2Seq Jasper graph (2 inputs, 1 output).

When I’ve tried to convert this graph to uff, I have got a lot of warnings, such as:

Warning: No conversion function registered for layer: FusedBatchNormV2 yet.
Converting ForwardPass/w2l_encoder/conv33/bn/FusedBatchNormV2 as custom op: FusedBatchNormV2

Does anyone know, or have experience preprocessing graph to convert into engine using TensorRT 7.0?