The FPGA is used to implement an approximation of the original hardware’s functionality - not a perfect clone of the original hardware itself, which means they have their own unique bugs and inaccuracies compared to the original designs.
I think “emulation” fits as a reasonable description of this, personally - at least as something an average person will understand.
I think “emulation” fits as a reasonable description of this, personally - at least as something an average person will understand.