What we are going to do is use winrar command line to archive all folders in a given folder in their own archive, split by ~50 megabytes, and then group all linked archives in their own subfolder.
Just set the harddisk drive letter and main folder and you’re good to go!
for /D %%s in (.\*) do "C:\Program Files (x86)\WinRAR\rar.exe" a -ep -ep1 -m0 -v50000 -df "%%s.rar" "%%s"
FOR %%F IN ("%origloc%\*.part*.rar") DO CALL :process "%%F"
CALL :checkpath "%~dpn1"
MOVE %1 "%subfolder%" >NUL
IF NOT EXIST "%subfolder%\" MKDIR "%subfolder%"