I don't really think it's possible, at least not with any general purpose solutions. By definition, VMs give you generic machines while routers tend be specialized machines with specialized chips.
Then when you start to factor in hardware nuances between router types (or even router revisions), nvram and wireless radios the scenario becomes even more complex. So the goal of reducing the risk of bricking a specific hardware model with an emulator is a bit of a stretch.
However you can run dd-wrt on an x86 images, and there are even ARM QEMU emulators (https://www.theregister.co.uk/2017/11/13/arm_emulator_in_a_vm/) available, so with a bit of effort I'm sure you can get DD-WRT running on them too.