Both of these "unique" moves do in fact build resource. Spinal's Ghostly Manual gives him a skull, and
Fulgore's auto triple gives a pip of energy. After that... Similarities are gone.
Spinal's ghostly manual is just that, a manual. Spinal can follow up a double with a manual, shown as a skeleton arm punching from the ground, by pressing the same strength as the double after it completes before the linker. Just like any other manual, they deal pretty ok damage, but are much harder to break.
Fulgore's auto triple is a bit different. Fulgore can perform three hits for his auto-double by
holding down the button he uses for that double. If the third hit connects without being broken, Fulgore gains a pip of meter for his Reactor Gauge. This cannot be done with manuals. It is more damaging than a regular double (as it is another hit), but it is easier to break.
I don't know any frame data as I'm not a high level KI player and only understand core mechanics... sorry. I believe there are ways in-game to get frame data, though. Hope this helps enough!
EDIT: Season 2 update tweaked these moves slightly:
Spinal now receives a skull on a ghostly manual (green attacks gives skulls).
Fulgore's new reactor system now makes it so he gets a great boost in reactor speed when landing the auto triple. The auto triple is now activated by pressing the button again, instead of holding it.