Finally it occured to me to sieve through the all the relevant EMF source on GitHub and I found that
Ransom All, Execute All, etc. was removed from EMF back in 2017. Unfortunately without any mention of it in the changelog or changing of the wiki, where it still prominently features. Geez, thank you guys for several days of confusion, trying to find an advertised but quietly removed feature!
emf_prisoner_decisions.txt on Github: "
removing ransom-all/etc. due to 2.7s QoL improvements" - Mar 14, 2017 commit by Zijistark (sorry, can't link yet as it flags as spam with my low post count or whatever)
I had a look at CK2 2.7 patch, and yes, it adds new Prisoner Management tool with filtering, but only as a paid feature for owners of MNM.
Is there any modding policy of not going against paid QoL improvements (quite understandable), or was it removed more by accident because Zijistark and other EMF authors own every DLC already and haven't noticed prisoner management tool (the "2.7 QoL improvement") was in the paid section of patch 2.7 with MNM DLC only? In case of the latter, would you consider adding the basic Ransom All/Execute All/Release All decision back into EMF again?
Now I'll just have to go through all the commits and see if I can mod it back just for myself. The MNM Prisoner Management tool looks great, filtering by all parameters, but I just need a simple Ransom All, nothing else. Clicking through thirty prisoners and waiting months between all the replies is just unworkable.
BTW, just in case to prevent any misunderstandings, I really like EMF, mods like these in HIP and others really make the game much more enjoyable It's just that looking for a feature that should be there according to text and changelogs - but isn't - is really confusing

Thanks!