That addon is not big thing. It's more about "making cloth" in Blender.Ok, I went full Sherlock with the add-on thing:
1. L&P announced that this update will have an "special thing".
2. L&P said that he got a helper for the 'special thing'.
3. L&P opened a thread asking how to incorporate a Daz character into blender without errors.
4. We can infer that the "special thing" was going to do by the helper in blender, but the helper didn't know too much about Daz, so, L&P did the research. The helper is a blender specialist and blender is mostly for animations.
5. L&P started to call the 'special thing' as add-on. We can infer that the helper told him that what he wants requires a blender add-on.
6. I searched blender add-on in youtube, there are too many.
7. I searched blender add-on here in f95zone and one took my attention:You don't have permission to view the spoiler content. Log in or register now.
Important are simulation and collision with other objects using the clothes already chosen by you.
Clothes come with a certain number of faces that intentionally are as few as possible. But simulation and collision needs more faces for good results. It's like trying to bend sheet metal but you want it to look like a coat.