There's many tools/projects make precomp and other compressors multi threads.
cls-precomp.dll made by BLACKFIRE69 seems to be the most stable one here
https://fileforums.com/showthread.php?t=103690
It calls precomp.exe not precomp32.exe not precomp64.exe
It can set precomp options in cls-precomp.ini
Other ones like MTX+precomp/other compressor crashes often for me, PMT+precomp/other compressor rarely works for me, same thing for PrecompX+precomp
/============
For final compressors, xtor, lolz and lzturbo already has multithread themselves, so I'm not sure if make them mt would have any gain, maybe even slower.
//===========
For other compressors, for example fl2 from
https://fileforums.com/showthread.php?p=483533
It is a very good compressor with good ratio and very fast speed. The exe version can be made multithread with
Universal CLS cls-pexp.dll (multi thread maker)
https://fileforums.com/showthread.php?t=103234
The Universal CLS seems to work great for those compressors like fl2.exe
Universal CLS can also make any other compressor multithreaded hence the name.
However I tried it with precomp, most of the time it works good but occasionally threads might lock up with each other and stuck there for minutes doing nothing before continue. Same thing happens to MTX+precomp but it locks or crash much often.
You'll still have to read, search the forum to learn about how freearc the ini such things