User Emunand9 or decrypt9 to dump emunand.bin from sysnnad
use same too to format new SD card correctly (can swap cards when in the homebrew)
Copy all the contents from old card to new card
Run decrypt9/emunand9 from sysnand
Restore emunand.bin to new sd
well there are two ways
1. you could always reinsert your old card and make a backup and then use the emunand.bin to restore the emunand to the new card like mentioned above
2. Or for whatever reason 1 isn't possible you can do what I prefer and follow this guide by Zaazu https://gbatemp.net/threads/how-to-transfer-emunand-to-another-sd-card-working-on-new3ds.383684/ this method will basically clone your sd card onto a new sd card of a different size
well there are two ways
1. you could always reinsert your old card and make a backup and then use the emunand.bin to restore the emunand to the new card like mentioned above
2. Or for whatever reason 1 isn't possible you can do what I prefer and follow this guide by Zaazu https://gbatemp.net/threads/how-to-transfer-emunand-to-another-sd-card-working-on-new3ds.383684/ this method will basically clone your sd card onto a new sd card of a different size[/QUOTE