Hi HazAT,
I actually think that you won’t need to do any special parsing for NativeScript exceptions. It seems that right now the reason field of an ObjectiveC exception is missing from the report and that the name is truncated to around 125/128 characters, but looking at the source code it seems that both are serialized without any truncation or other modification. See SentryException.
My guess is that this happens somewhere else and not in the Sentry API.