Who are some of the Koha-Ace characters in the ED?
I believe the one on the far left is Kariya Matou from Fate/Zero, 



the one next to Chikagi is Rani VIII from Fate/Extra (it's a bit hard to see as reface is mostly obscure, but the clothing and skin color matches), 



and the one in front of Miyako is Assassin (Li Shuwen), also from Fate/Extra (the wardrobe practically gives it away).