I don't know. I probably can't do better than cube explorer:
r F2 U2 r' B2 l B2 r D2 l' E2 B2 l' y2 (13)
, which is equal to what we can already do using "LU'F (PLL parity) F'UL'", assuming that we use a PLL parity algorithm like r2 F2 U2 r2 U2 F2 r2, so that it can be applied to all size cubes. If not, for the 4x4x4, 12 may be the minimum.