Yeah RRL search engine for kingdom building sucks. And they don t plan to just add the damn tag either.
LOL if you don't want it to be in NU you're clearly looking in the wrong place personally i haven't read any kingdom building stuff from western authors, but i guess i'd like to give it a try...if you find one pls post it here
The Overlord of Blood and Iron -> Only a few chapters before translator went missing but I this is better than Lord’s Empire and World Online you mentioned.
https://www.novelupdates.com/series/dungeon-defense/ Is dungeon building okay? It's Korean, not Jap. https://www.novelupdates.com/series/tensei-shitara-slime-datta-ken/ It's jap, but he makes a city of monsters.
Rise of the Lord is the newest one with good quality writing and plot I've found. RRL link in case you're at war with Qidian: rise of the lord