Hmmm, so a 68k JIT emulation engine is emulating a second 68k interpretive engine.
Interesting.....
Am I correct in assuming that Sheepshaver virtualises the 68k CPU?
amithlon support running x86 code, so you could port winuae. talking to the os requires an endian conversion, but there is a build of gcc that supports that.
The 68k macos on 68k amiga emulations generally work by patching macos to run as a user process. There are a few things you have to do to stop it conflicting, but it doesn't really count as virtualising.