Sorry, don't have them, but it seems that Sarcophyton and Sinularia are quite big for 12 g, you'll need to frag, and frag, and frag... And, as I had read, sinularia are one of the most active in chemical warfare.
Why I'm telling this: I acquired branching hammers and frogspawn as a suitable for 6g nano, well - they expanded too big in a few months; nice 3" doughnut brain became 7.5" in a few months...
And brain-type LPS started to look better in a separate tank, without soft corals and filter feeders, could be coincidence, of course.
If you just like leathers - it's your choice, but if you are looking for low light durable corals - these did well in my 6g Nano-Cube with 18W: white xenia, green star polyps (on the top, close to the lights, and surround it by LR rubble or shells from dollar store, to prevent spreading on surrounding rock), neon-green candycane (other candycanes are more light-sensitive and have longer tentacled, this one is harmless, IMHE), hairy mushroom with green base and pinkish "hair" (will be 2.5 in in a year), bright red mushrooms will be also OK, only closer to the lights. And, as I said, hammers (the cold green with compact heads is preferable to yellowish-green with shapeless heads) and frogspawn (green body, pink tips) too, at mid-level or higher - only place them that flow will not move their tentacles onto other corals, onto left slope, may be.
And fluorescent-blue bushy algae Ochtodes too.