These are the list of Xbox1 games I owned and already tested/playable with my Xbox360 (NTSC-J) ~Using Latest Backward compatibility update November 2007:
1- Ninja Gaiden Black (support wide screen)
2- Crimson Sky: High Road to Revenge (4:3 Screen)
3- Fatal Frame II: Crimson Butterfly (4:3 Screen)
4- Soul Calibur 2 (4:3 Screen)
5- Forza Motorsport
6- Rogue Troopers (Support wide screen)
7- Splinter Cell: Chaos Theory
8- Spyro: New Beginning (suppot wide screen)
9- Dead or Alive Ultimate (support wide screen)
10- Halo & Halo2 (support wide screen)
11- Phantom Dust (4.3 Screen)
12- The Lord of the Ring: Return of the King (4.3 Screen)