The standard army roster for the Skaven includes units from all the Great Clans as well as the rank and file from the Warlord clans. Therefore, they only include the units that stand out from the Great Clans instead of the normal rank and file, because that's what makes them stand out in the sea of rats.
In 6th Edition, there are specialised Army Lists for all the Clans, and Storm of Chaos gives you an Army List and Army rules for running Clan Eshin. That is also where the Eshin Triad unit consisting of three assassins working together that DL used came from. Eshin Sorcerors are also part of that Army List, except all they had was Skitterleap, Lore of Stealth never made it to the tabletop. However, Lore of Stealth did make it to Total War Warhammer II.
The Eshin Army List included the following units: Master Assassin, Chieftain, Assassin, Eshin Sorceror, Night Runners, Clanrats, Clanrat Slaves, Stormvermin, Rat Swarms, Gutter Runners, Giant Rats, Warplock Jezzails, Eshin Triad, Plague Monks, Plague Censer Bearers, Poisoned Wind Globadiers and Dogs of War (Dogs of War are available for almost every Army List. Gotta make money).
If you think this is one note, wait until you find out about the roster for the Slayer Army of Karak Kadrin.