If put you a whole PowerUP card on an FPGA then OS4.x and older versions of MorphOS would run on it. Still agree that it would be a waste of time and resources.
.. or grab an old G4 Mac from the garbage retail shop aka ebay for less than peanuts and install a current version of MorphOS on it. Maybe not as freaky as on a 80ies computer pimped with an FPGA, but way cheaper, straight forward and more powerful.
I really like Vampire and am considering to equip my A600 with one, but definitely not for MorphOS when there are actually fast machines available (which cost quite less than the very nice and fair priced Vampires).