Easiest way to add vertices to a mesh edge?

[Darklocq]

What's the simplest way to add vertices, specifically to inject them into an existing edge, between the original two vertices that defined it?  I'm an Outfit Studio and NIFSkope user, and have zero experience (yet) with Blender or 3DSMax.   What I have is a skirt/kilt   All I want to do is add additional vertices along the vertical pleat lines so that it will flex more like real cloth.  Presently, each of its pleat edges, vertically, is a single straight line from top to bottom; it cannot bend and flex like real cloth, all it can do is flare outward with movement but very stiffly.

 

Basically, I have this (laid out horizontally instead of vertically for ASCIIart reasons):

*-----------------------------------------------------------------*

 

And want to change it to this, consistently on every long vertical edge that defines the garment so it no longer moves like something from 1995 gaming:

*----------*----------*----------*----------*----------*----------*

 

This is probably a "Wow, you are a mega-noob" question.  I'm not stupido, I just have not yet had any cause to do anything like this.  I can form-fit stuff like mad in Outfit Studio, create super-tweaked realistic BodySlides, retexture ugly gear, patch 5 conflicting mods in TES5Edit, etc.  I just know fuck-all about materially changing or creating meshes.  I've looked at various tutorials but they all seem to be about animation or about creating something from scratch, or about splicing and mending different meshes to do a mash-up.  Even if I find, say, how to do this in 3DSMax, for all I know this can be done in NIFSkope, or it is much better done in Blender, or there's some script that can automate it and save hours of work, or yadda yadda.  So I ask, since this place seems to be overflowing with 3D experts with a lot of gear-modding experience.