Specifically, images like these. I found them for the original 8 factions, but I'm looking for the ones made for the dlc factions, or for the official source of all of them, so I can look at them all in one place?

I'm just getting into endless legend and the universe and world building is something else. 

If you are searching for lore in one place you should just start at wiki:

https://endlesslegend.gamepedia.com/Endless_Legend_Wiki

I know that the wiki is an option but I don't feel like looking at walls of text on a white background. I guess I'll just find a youtube video. Shame they got rid of this material, since they still updated the game up to 2019 (and maybe more will come in the future). 

don't feel like looking at walls of text on a white background

Yeah, books are hard for zoomers