Haze homebrew edited to run as sysmodule. Just plug USB and it's connected as MTP.
Original homebrew source code:
https://github.com/Atmosphere-NX/Atmosphere/tree/master/troposphere/haze
Requires 2.2MB of RAM to work.
You can turn it off and on with Sysmodules overlay.
https://github.com/ppkantorski/ovl-sysmodules/releases
If you want to add custom paths as partitions, create config.ini in sdmc:/config/sysHaze/ and write there
[Name]
Path=FolderPathf.e.
[FPSLocker]
Path=SaltySD/plugins/FPSLocker/patches
[Contents]
Path=atmosphere/contentsMax 8 entries is allowed.