@Mega Man Volnutt Yup, that's possible! However it'd mean replacing over the dead pose, so that'd no longer be an option for any custom characters, if you're cool with that.
:cutesmile: You'd also only be able to use a one-directional sprite with 3 frames, just like how the dead poses work. (Editing the plugin to have more options may be possible, but that's outside my scope I'm afraid!)
Replacing the dead characters can be done all via the images, no need to mess with any plugin parameters or filenames! Locate your game folder img>Sumrndmdde>character-creator-ex. These are split up into layer parts, and then divided into the types. We're interested in all of the 'dead' folders.
So I've been playing around with this plugin for the past couple weeks and was able to add additional poses but it is kind of a PITA and requires a lot of editing of the plugin file. Basically you need to add new sections for each pose in the plugin file. Do a search for "dead" in the plugin file and every time that term comes up, you also have to make an equivalent section for your new pose.
For example, I copied the "dead" section here and made an "attack" section (under the //edit note)
HOWEVER, if your pose is four directions (instead of 1 like the dead sprite) you need to copy the base/walking functions instead for a couple sections.
For example, I copied "buildBitmap" to make "buildBitmapAttack" instead of copying "buildBitmapDead" because I wanted four directions for attack

Then you also need to make "attack" (or whatever pose) folders with all the associated parts in them for everything (body, clothes, etc).
To change your custom character to the new pose use the following scripts:

Where 1 is the actor number. If you want to change back to the normal walking sprite change true to false in the first line.
Do you have to do all this work?
Yes, after all, all that work was done to add the dead pose in the first place. It's either that or overwrite the dead pose like Rhino said, but then you don't have the dead pose and are restricted to one direction.