Re: arrow conversion unit? yes i said arrow!
Gee whiz nifty, but stoopid.
Shoots arrows, but not archery (arch-from arcus= bow).
Not legal for game (as opposed to nongame) hunting during an archery season anyplace I can imagine.
Rimfire, so not legal if rimfire prohibited for the quarry in question.
Noisy compared to a traditional (as opposed to compound) bow. Over more than a few yards the game will be in motion before the arrow arrives.
Controlled as a firearm because it is a firearm.
Arrows were considered as valid projectiles for firearms.... 5 or 6 centuries ago (harpoon guns excepted).