How to convert syncbn to batchnormND?

I want to run a model with syncBn in cpu, so I have to convert syncBN to batchNormND, how can I do that?
I just found a way to convert from bn to syncbn, but how to do the opposite? Thanks in advance.

I think the best approach would be to not use convert_sync_batchnorm in your model, which should be executed on the CPU.
Would this work or why do you have to apply this transformation?