At least if you going to call it 'emulation' then all forms of flashcarts that use FPGA technology to replicate different hardware, chipsets and 'mappers' are 'emulating'.
Which isn't helpful (and is confusing) to people who are looking for something that isn't the same thing as software based emulation that are on most PCs, Raspberry Pi, clone systems.
Yes even Higan tries to emulate all aspects of hardware, but it does require a very powerful computer to do so, so unless you have a really powerful system it will run with extra lag unlike actual hardware. But most emulators don't do that.
Lumping it all under 'emulation' just makes it needlessly confusing, where people are trying to understand 'what the difference is'.
I do know it will becoming really interesting when SD2SNES Pro starts supporting onboard Super Gameboy, in other words replicating an entire alternate game system on the FPGA itself, and not just a 'chip'/'mapper' (the original Super Gameboy is gameboy hardware stuffed inside a cartridge with other chips, and its own rom to communicate with the SNES).
Interesting discussion here...
https://www.reddit.com/r/emulation/comments/7vjehj/fpgas_arent_magic_an_article_by_the_creator_of/
