I'm affraid I cant find any good screenshots of the korean units in Empire: total war.
I did find some videos on youtube though, here is one of the Korean campaign featuring Yi Sun-Sin.
https://www.youtube.com/watch?v=7v09Az-doLYSadly the uploader cancelled the first cutscene, but later in the video the cutscenes are not skipped and give a better view of some units. Basicly everyone who talks is a story character though and not recruitable, but soldiers can be seen in the background here and there.
It's a pretty nice game though, I can really recommend it. The campaigns are interesting enough as far as strategy games go.
All armies are unique as well, no faction shares the same unit. Even workers look different.
The time periods used are medieval, gunpowder age, imperial age, ww1 and ww2.
Medieval to imperial has the civilisations Franks, England, Korea and China playable. ww1 and ww2 has Brittain, France, United States, Russia and Germany playable.
It can be selected what epochs are included though for skirmish, and in the campaigns its typically one epoch.
The jump from imperial age to ww1 is where a civ chooses between several choices what faction to change into.
I gues thats a bit quirky, but I like that they have chosen to do a few factions and time periods properly instead of trying to do everything and do it poorly.
I'm sure you would enjoy the Korean campaign story though! There are also two other playable campaigns focusing on Richard Lionheart before the crusades, and General Patton in WW2.
