Isn’t that what I’m doing?
Mac OS is arm64, with an arm64 Ubuntu VM, then I’m running qemu in that for specific single x86 processes.
To clarify, I’m using UTM to run the VM, so it’s using qemu - but it looks like that doesn’t give you a performance cost in itself.
Forget about full system emulation, especially with Qemu’s approach which doesn’t leverage the host MMU. Emulating an MMU alone is very costly perf-wise. That means that you should use an arm64 OS and then use an x86 compat layer on it.
For Qemu’s user mode emulation, it doesn’t exactly provide good performance either. But it is still much better than full system emulation.