Maybe it's more of a hypervisor since the 3DS has DS hardware. Some time ago, we thought there was no way to emulate GBA on DS, but gbaemu4DS would eventually run relatively decently.
if it's based off of desmume or another emulator it's not a hypervisor. but an emulator. but if the cpu architecture is close enough less work has to be made in recompile, I think?
However DS emulation on 3DS is pointless as running Citra through HBL.
you know of nintendon't to play gamecube games on Wii or Wii U (in wii mode though)
wireless controllers and virtual memorycards, the benefits om emulation but it's not emulation. and you only need one console not 3!