TBH I'm more interested in the skin textures than the models themselves for the most part, so if they're custom models using textures found elsewhere, that would be fine!
These are definitely DAZ Original characters, and often even without mixing. You'll have to look through them all yourself and after an hour you'll find them.
So far I've figured out that the Side Part black-haired model is Snow Queen, and the Crimp Ponytail models are Olympia and Kala. The other two are giving me some trouble still.
Black-haired side part char from second link is Joan 9 HD with High Elf Add-On
h**ps://www.daz3d.com/joan-9-hd-high-elf-add-on
Other MATs (blonde char, etc) seems same texture. Brunette in first link (first model/image) could very well be standard Joan 9 HD MAT.
There seems no evidence of much other postwork in renders, just original MATs with DS lighting - opinion.