A Big battle in Skyrim??? Impossible
Spoiler i killed so many of the own guys in close combat at Whiterun. They are running straight between you and your enemy and you easy don't look through the people which is your own, which is an enemy.
As a counter point, I did all of the Stormcloak quests and not a single one of my men fell at my hand. That is definitely related to how good a player is at picking targets, aiming, and attacking. Besides, M&B has the exact same issue of all the soldiers looking the same (More so than Skyrim, I can easily pick off the one guy in red armor surrounded by my allies in blue) and the exact same risk of friendly fire.
Edit: And I'm just going to point out now that M&B has the battles and combat style the OP is looking for, and has the ability to make custom maps and add your own quests and such. It's much more feasible to port the world of Skyrim (Or all of Tamriel) to M&B than it is to port the game mechanics of M&B to Skyrim.