sys-ftpd-light VS ftpd

Try https://github.com/cathery/sys-ftpd-light. It's super convenient.

I recommend sys-ftpd lite (which runs in the background), https://github.com/cathery/sys-ftpd-light you need to edit the config.ini located in config/sys-ftpd/config.ini you can configure the user/pass or just enable anonymous:=0 then you can use a client like filezilla, winscp or windows ftp to access your switchs sd card with your switchip:5000 u/ToxiClay you should try this too.

yes you can use FTP, either https://github.com/mtheall/ftpd or https://github.com/cathery/sys-ftpd-light, you still need to transfer your files prior, also you can mount your switch via usbc cable using tegragui, I also believe there's a homebrew app that allows you to access the microsd card via usb cable https://github.com/retronx-team/mtp-server-nx i think

tried to make sys-ftpd-light function, but it still won't.

you can interact with your SD card without taking it out using FTPD

Run sys-ftpd or ftpd and access your files from a computer using an FTP client

Use FTPD for quick file transfers to the 3DS over wifi without the need of removing the SD card. Available in the Universal Updater app.

FTPD: https://github.com/mtheall/ftpd/releases

I don’t have what you’re looking for but I have a solution for your screwdriver problem. Here is a video explaining how it works.

I have ftpd on my 3ds and I use FTPCafe FTP Client on my Android phone, then i download DS roms on my phone, after this I share internet (hotspot) to my 3DS, start ftpd on it, then put the IP that it says on the phone.