It happened again, I've found a patched ps3 iso on one of external HDDs and forgot how I've patched it.
After a couple of hours of searching I found a commands to do this and also found a program which can do it.
So the story is that there is a huge archive of PS3 games https://myrient.erista.me/files/Redump/Sony%20-%20PlayStation%203/
but ISO will not run on CFW because it's protected. Website stores only clear dumps of blue-ray disks.
Main option is to have encrypted ISO: https://myrient.erista.me/files/Redump/Sony%20-%20PlayStation%203/
First of all the software https://github.com/al3xtjames/PS3Dec
Second - the keys
https://myrient.erista.me/files/Redump/Sony%20-%20PlayStation%203%20-%20Disc%20Keys%20TXT/
I have a zip file on my machine with all those keys. But I don't remember where I've downloaded them back in 1-2 years ago.
Compile PS3Dec for your OS.
and launch it
./PS3Dec d key XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX /home/user/Games/PS3/one_piece_pirate_warriors_3_eu.iso /home/user/Games/PS3/one_piece_pirate_warriors_3_eu.patched.iso
If everything went smooth copied ISO on PS3 should be visible for Multiman and will be mounted and executed without any issues!