You could try: 6123A/B/C 5[2]36A/B/C
While you hit the first button got back to 5 and make sure you're holding 2. Then roll the 36 and hit the second button. It's easiest to make sure you do the 2nd motion while the last attack is happening. Zaelar would know buffer input tricks better than me though.
I don't know jack shit about Nanaya's combos, either. I had to do something similar with Ryougi.
A good way to practice tough links is to always think about what you're doing. If something didn't link/work, (even if it happened once in like 4-6 times) just try to do each one a little different until you find the sweet spot. Don't keep trying to do the same thing wrong.
When I was learning stick I went through a million little buffer tricks. I don't know what input you're using, but if it's on stick there is always an easier way to do it, ergonomically.