Originally posted by JRG1988
If there is no advance mode, there is no possible way to change the region to US. Any game with any online competitive modes whether it's just leader boards or online competitive play will have advance mode disabled unfortunately.
I think there´s very few exceptions such as RER 2.
EDIT:
Okay, got the plat due to some nice random who knows how to play the game 1000x better than me lol. Just a little addition: For Save 20 (getting the legendary weapons) just enter and exit the shop over and over again until you can buy the pale rider (badass magnum). Buth trophies will pop, no need to play through raids and collect weapon crates. And one more thing: All trophies popped as intended, even save #18 (read trophy descriptions first, e.g. the lvl50 weapon trophy doesn´t pop automatically you have to actually pick up the weapon).