I'm not sure that a emulator like they had the previous two transitions is needed this time. The software stack is much more prepared this time. The long tail of abandoned, legacy applications is already shed, and everything running in current macOS is built on a toolchain with excellent ARM support, including the majority of open source products. Applications in the Mac App Store is at worst a recompile away, and many can be recompiled by Apple in the store itself. Everything on iOS/iPadOS is already 100% ARM based, and everything passing through Xcode will recompile just fine to ARM. Mostly everything Microsoft does is on a toolchain supporting ARM, due to its own platforms, but also Android and iOS. The only thing I worry about are those depending on using x86/Windows. Not Apple's priority at all