Other than some cosmetic differences?
Moore is a SAF/Gura case filed in the Central District and is being argued mostly on a point of law. Sheppard is a NRA case filed in the Southern District and has a more emotional argument.
But because they are filed in different districts, they can not be combined.
Now should a (bad) decision be reached in both cases at more or less the same time, then expect them to be combined at the Circuit level, on appeal.