Unless you know something I don't, VirtualBox isn't qemu's CPU emulation - it's only virtualization for the current CPU. So, great if you want an alternative to Virtualization.framework but it's not going to run Windows 7 on Apple Silicon

And, even if it did run effectively under Rosetta, its management interface won't even let you select a non-arm64 guest: https://www.virtualbox.org/manual/topics/Introduction.html#h...