Answering my own previous question, if the parameter -m2 would be passed normally using {:
option} as a parameter of the XTool 2020 (ue4 plugin), which was in doubt because it had only tested with Borderlands 3 that uses -m1.
The answer is yes, it worked perfectly, look at the results.
Code:
Rune II sample Rune-WindowsServer.pak
xtool_zlib = XTool 2020 -mzlib
xtool_ue4 = XTool 2020 -mzlib+ue4
Test 01 = srep+lzma2
Compressed 1 file, 1,494,084,687 => 1,181,272,582 bytes. Ratio 79.06%
Compression time: cpu 1.80 sec/real 110.29 sec = 2%. Speed 13.55 mB/s
Test 02 = ue4dt+srep+lzma2
Compressed 1 file, 1,494,084,687 => 619,066,054 bytes. Ratio 41.43%
Compression time: cpu 1.72 sec/real 338.60 sec = 1%. Speed 4.41 mB/s
Test 03 = ue4dt+xtool_zlib+srep+lzma2
Compressed 1 file, 1,494,084,687 => 618,955,970 bytes. Ratio 41.43%
Compression time: cpu 2.06 sec/real 348.92 sec = 1%. Speed 4.28 mB/s
Test 04 = xtool_ue4(-mzlib+ue4)+srep+lzma2
DiskSpan_GUI method = xtool_ue4:m2:k0x5DD20432F2AD810071033FC3F925FFDFD647514524D0A0D222E17D76BAF57BFD+srep_new+lzma2
xtool_ue4 = Arc.ini setting
packcmd = "XTool.exe" precomp -mzlib+ue4{:option} -c32mb -t100p -d1 --dbase - - <stdin> <stdout>
Compressed 1 file, 1,494,084,687 => 545,149,382 bytes. Ratio 36.49%
Compression time: cpu 1.84 sec/real 179.33 sec = 1%. Speed 8.33 mB/s