A major hole

Nearly all assault weapons bans define assault weapons in terms of being semiautomatic. The proposed 2019 ban is no exception. It defines "assault weapon" like so:

The term `semiautomatic assault weapon' means any of the
following, regardless of country of manufacture or caliber of
ammunition accepted:
            ``(A) A semiautomatic rifle that has the capacity to accept
        a detachable magazine and any 1 of the following"

There is a huge hole that can be exploited.

Federal law defines semiautomatic rifle thusly:

 The term “semiautomatic rifle” means any repeating rifle which utilizes a portion of the energy of a firing cartridge to extract the fired cartridge case and chamber the next round, and which requires a separate pull of the trigger to fire each cartridge. (emphasis added)

The same definition of semiautomatic applies to pistols and shotguns under that same AWB.

The weakness here is obvious. All you need to do is have something other than the energy of a firing cartridge eject and load the next, and the weapon is no longer subject to the AWB. It seems like Franklin Armory is trying to do just that.