ok, so basically, just download the system fw cias for the region you want.
if you are on 4.x, i recommend to download the 5.0 cias. you could download the 9.x ones straight away but then you will have to worry about not getting the n3ds fw titles too. with 5.0 you do not need to worry about that.
go to devmenu, install the cias, and turn off.
go inside the nand, replace the SecureInfo_A (sometimes_B) file with the one from the region that you want to change to. (this will change your console id to that console, i guess it would also 'unban' you if you are banned, like you could use the file from a 3ds of your same region, so, jpn-jpn, and it would unban you etc)
you can tidy up the nand by deleting the system fw titles that do not exist in your new region that you changed to. - i made a small python tool to check and find the differences, i could also make it automatically delete them for you, but that would only really work for me on mac since i can mount the fat16 partiton nicely by naming it '.iso', on windows i doubt it is that simple etc. - anyway it is not required to delete the unneeded leftover system titles but you will have duplicated of stuff, like camera, system settings... etc etc. also things behind the scenes as well.
when you boot up you will be in the new region, and you can update to the latest fw if you want.
eshop might work, some people said for them it worked first time, 'lucky', but try the little guide i shared above.
this can be done on sysnand or emunand. (but if we were to get gw to patch the function, or get that done in a CFW, then it would not be possible on sysnand without using a legit file form another 3ds
i made a tool to dump and inject the SecureInfo_A file from sysnand/emunand, it only works for sysnand 4.x, i can share it soon
麻烦大神翻译下不过我看出工具似乎是没发
另外是一个叫cearp的人发的，也就是多玩论坛的王blueblue
if you are on 4.x, i recommend to download the 5.0 cias. you could download the 9.x ones straight away but then you will have to worry about not getting the n3ds fw titles too. with 5.0 you do not need to worry about that.
go to devmenu, install the cias, and turn off.
go inside the nand, replace the SecureInfo_A (sometimes_B) file with the one from the region that you want to change to. (this will change your console id to that console, i guess it would also 'unban' you if you are banned, like you could use the file from a 3ds of your same region, so, jpn-jpn, and it would unban you etc)
you can tidy up the nand by deleting the system fw titles that do not exist in your new region that you changed to. - i made a small python tool to check and find the differences, i could also make it automatically delete them for you, but that would only really work for me on mac since i can mount the fat16 partiton nicely by naming it '.iso', on windows i doubt it is that simple etc. - anyway it is not required to delete the unneeded leftover system titles but you will have duplicated of stuff, like camera, system settings... etc etc. also things behind the scenes as well.
when you boot up you will be in the new region, and you can update to the latest fw if you want.
eshop might work, some people said for them it worked first time, 'lucky', but try the little guide i shared above.
this can be done on sysnand or emunand. (but if we were to get gw to patch the function, or get that done in a CFW, then it would not be possible on sysnand without using a legit file form another 3ds
i made a tool to dump and inject the SecureInfo_A file from sysnand/emunand, it only works for sysnand 4.x, i can share it soon
麻烦大神翻译下不过我看出工具似乎是没发
另外是一个叫cearp的人发的，也就是多玩论坛的王blueblue
