True, but it would likely be very slow. Although perhaps it could be improved a bit by using dynamic translation.
(And of course, strictly speaking, it's not possible to emulate the same model of calculator that the emulator is running on. Some parts of RAM and/or Flash - the emulator's code and internal state, as well as the files that you don't want the emulated program to be able to modify - must either be somehow inaccessible to the emulated calc, or immutable.)