It is well known that the fastest stalemate is in 9.5 moves, aka 19 ply. But what is the fastest stalemate possible if all of the pieces, not pawns, are allowed to be shuffled on their respective ranks in any mannner? There are a plethora of possible positions to consider, making this task extremely difficult, but 19 ply can surely be beat from some position.
I don't know if this is the fastest, but I managed to shave one ply off of the standard chess example by moving the queen to a better starting square. This allows the side giving stalemate to start capturing one move sooner, resulting in stalemate in 18 ply instead of 19.
[Result "1/2-1/2"] [FEN "rnbnqbkr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQ - 0 1"] 1. a4 d6 2. Ra3 Qxa4 3. h4 h5 4. Rah3 Qxc2 5. f3 Qxd2+ 6. Kf2 Qxb2 7. Qxd6 Qxb1 8. Qh2 Qxc1 9. Kg3 Qe3 1/2-1/2