No, we do not have any LW SFP+ transceivers available on the FC interface, for the HNAS 4000 series (LW SFP's are available on the cluster links and host connections).
Whilst an HNAS 4000 2-node cluster supports a max of 2 different arrays in direct attach mode, the expectation for HNAS (in a stretched cluster) is to have a fabric on the FC interface.
Generally speaking, there are two host groups created on the "same" target port on each array, and one of those host groups has HMO 78, so the servers know which port is the "remote" port. In a DAS configuration, there could only ever be a single FC host port connected to a single FC target port, which then precludes the HNAS FC ports from seeing a common target port.
I cannot recollect whether an HNAS stretched cluster, using GAD, will work in direct attach mode (I have no references to it on our specs or past testing) or whether this topic has ever been discussed in the past.
I think the tried and true method is to use SW SFP's and add multiple FC fabric switches at each site/DC. There are many similar installs in the Central EMEA area in this configuration.