A opção -mnt:on
está simplesmente errada, pelo menos com meu 7-Zip 18.05 (x64)
este lote:
:: Q:\Test18\SU_1365974.cmd
@Echo off
Set z7="C:\Program Files-Zipz.exe"
Set "z7o=a -y -r -t7z -m0=lzma2 -mx=9 -mfb=128 -md=512m "
for %%F in (*.rar *.zip) do (
%z7% x -y -o"%%F_tmp" "%%F" *
pushd %%F_tmp
%z7% %z7o% ..\"%%~nF".7z * ||(pause)
popd
rmdir /s /q "%%F_tmp"
Rem del "%%F"
)
(remova o Rem na frente do del para excluir o arquivo original)
Produziu esses resultados em arquivos zip de amostra, principalmente a partir de uma instalação de arduino.
> dir
Datenträger in Laufwerk A: ist RamDisk
Verzeichnis von A:\
2018-10-11 20:22 533.163 1802-064.7z
2018-01-27 15:38 535.890 1802-064.zip
2018-10-11 20:22 265.703 Adafruit_Circuit_Playground-1.6.9.7z
2017-10-21 18:06 408.442 Adafruit_Circuit_Playground-1.6.9.zip
2018-10-11 20:22 294.031 Adafruit_Circuit_Playground-1.8.0.7z
2018-03-09 19:39 472.998 Adafruit_Circuit_Playground-1.8.0.zip
2018-10-11 20:22 24.213 Adafruit_NeoPixel-1.1.3.7z
2017-11-30 20:26 36.399 Adafruit_NeoPixel-1.1.3.zip
2018-10-11 20:22 27.574 Adafruit_NeoPixel-1.1.6.7z
2018-03-09 19:39 40.682 Adafruit_NeoPixel-1.1.6.zip
2018-10-11 20:22 18.280 APA102-2.0.0.7z
2017-09-09 14:30 25.694 APA102-2.0.0.zip
2018-10-11 20:22 794 archive.7z
2018-09-24 14:13 1.582 archive.zip
2018-10-11 20:22 128.390 ArduinoJson-5.13.1.7z
2018-03-09 19:40 242.718 ArduinoJson-5.13.1.zip
2018-10-11 20:22 17.001 AS_BH1750-master.7z
2017-12-15 15:17 31.034 AS_BH1750-master.zip
2018-10-11 20:22 489.473 avrdude-6.3.0-arduino9-i686-w64-mingw32.7z
2017-11-23 20:43 645.974 avrdude-6.3.0-arduino9-i686-w64-mingw32.zip
2018-10-11 20:22 31.008 Bridge-1.7.0.7z
2018-01-05 22:14 61.431 Bridge-1.7.0.zip
2018-10-11 20:22 14.761 DallasTemperature-3.7.6.7z
2017-09-09 14:30 27.378 DallasTemperature-3.7.6.zip
2018-10-11 20:22 14.811 DallasTemperature-3.8.0.7z
2018-03-09 19:40 27.988 DallasTemperature-3.8.0.zip
========= =========
.7z .zip
Cumulated size: 1.859.202 2.558.210
percent of the other 73% 138%