You should replace Return with Rock Slide or Power-Up Punch. I used physical Greninja two or three times and it was fun. I remember I Rock Slided and OHKO'd a Charizard or something and it felt great.a fun gimmicky set to catch people off guard is banded greninja
Greninja Choice Band
Jolly
252 Atk/252 Spd/4 HP
-Return
-Waterfall/Water Shuriken
-U-turn
-Night Slash/something else
good to shock those florges / other special walls that want to switch in on greninja, and 95 base attack is passable.