I've been trying to use a HFS partition from a hard disk taken from my classic system with Basilisk II. I connected it to my Efika through a IDE->USB cable.
The disk works just fine and I can see all the partitions on Ambient. All of them except for the HFS one. I guess that's OK because I need this partition only for emulation, but - since it's not seen - Basilisk won't see it too.