7zip Ultra LZMA2 compression

Your command line should be at least:

7z a -t7z Files.7z -m0=lzma2 -mx=9 -aoa

Note that you'll get better compression when using 1 or 2 threads, not 8. So, even closer to your GUI settings (ms : solid, d : dictionary size, mhe : encrypt header (file names), p : password)

7z a -t7z -m0=lzma2 -mx=9 -aoa -mfb=64 -md=32m -ms=on -d=1024m -mhe -pSECRET

It's hard to get the same result, but this is the best I can get so far:

7z a -t7z Files.7z -m0=BCJ2 -m1=LZMA2:d=1024m -aoa