Specify which CPU an app uses

Greetings.
I am thinking ahead to a possible hardware upgrade for my TrueNAS setup. The new system will have two CPUs and a video card for Plex transcoding. The problem is the x16 PCIe slot is specific to the CPU2. Because the video card will be tied to CPU2, it makes sense to me that the Plex app should be using cores from CPU2. I see in the Docker documentation that option “–cpuset-cpus” allows this. I am using the official Plex app; is there a way to pass Docker options?