I just tried it on a blank project. Default kick drum play 4/4 and only Violet on the master. Adding the plugin increased FL CPU from 1 to 21. Enabling fixed size buffer didn't alter the CPU. I can't see a "Multithreaded processing OFF" option anywhere.
I was making the point that, in my experience, FL can't handle as many demanding plugins as another DAW. It will red line and cut out way earlier than Reaper, for example. Guarantee that if it's showing 80% in FL's CPU meter, it'll probably be less than 20% in another DAW.
Edit: none of the plugins on that list, no.
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