I would say that it is absolutely possible and that often the amount of new things to learn won't be that much different than if you would stay on high level but move into a completely different business domain.
As some minimum requirements I would say you should have some solid C and C++ knowledge and a good understanding of how computers work in general (what are cpu, memory, etc. doing, what are interrupts, processes/threads/scheduling/synchronization, common bus systems like uart, i2c or spi, ...).
If someone is looking for a very specific/niche skill set, then they most likely won't find a suitable employee. So for me it would totally be ok if someone is not yet an expert in the domain but is very motiviated to learn it and if he doesn't expect to get expert position in the beginning.
From your perspective it might also make sense to make some gradual transition where you still can partly leverage some of your existing skills. E.g. working on embedded devices that are powered by web interfaces (lots of them in the meantime), where you find everything from developing user-space applications which utilize a vast amount of networking down to kernel stuff. Moving directly to deeply embedded stuff (FPGA code, DSP programs, feedback control systems) might make less sense, because you would need more of an EE background for it.
Regarding your question if we directly know someone: Where are you located and how fixed are you on that?