I don't think there was ever a "just have it powered with the file on the SD card" type method.
There should be some hacked firmwares for the 3ds though that drop the backwards compatibility layer back to some of the earlier ones with protections, might even be some that get rid of them entirely but I have not been following things there. If you want to use the EZ5i anyway with a 3ds you will likely be wanting that anyway as the final DS flash cart killer update also took out the EZ5i and we did not see a workaround for it.
There should be some hacked firmwares for the 3ds though that drop the backwards compatibility layer back to some of the earlier ones with protections, might even be some that get rid of them entirely but I have not been following things there. If you want to use the EZ5i anyway with a 3ds you will likely be wanting that anyway as the final DS flash cart killer update also took out the EZ5i and we did not see a workaround for it.
