Ok that makes sense now. Been so long since I’ve been ok the industry I forgot about this stuff.
Would it be possible to access the shares through both a FC connection and Ethernet to clients? Or would the FC connection not work through samba and I’d have to go the iscsi route?
Optical tech doesn't make them compatible. Think: diesel vs gasoline. Yes they're both liquids. Don't mix them up though.
Samba implies SMB filesharing which is a protocol where the filesystem resides on the fileserver (=NAS) and you communicate using IP (=Internet protocol) over Ethernet.
iSCSI implies block storage which is a protocol that acts like a big USB drive. The filesystem has to reside on the client (=Windows/etc) and you could potentially communicate via FC but TrueNAS doesn't officially support that. Most filesystems are not "cluster aware" which means that it isn't a sharing protocol, you can only run one filesystem at a time on an iSCSI device, so also only one client at a time. Just the same way it's impractical to hook up a USB HDD to two PC's at the same time... doesn't work.
Basically your last sentence makes no sense in the realm of possibilities.