Izumo: Takeki Tsurugi no Senki

Both series involve a group of friends and classmates are transported to another world.IN both series the male lead's rival sides with the bad guys while the male lead and everyone else sides with the good guys. 

Well they both have people traveling to another world they also have the whole war thing which involves humans against demon/evil ghost  

Highschool students gets transported to another world. They must find a way back home and solve this world's situation  

It's obvious, both have teenagers transported to another world with hot girls, best friends fighting each other on different groups. Both are good and if you like one then you'll like the other. xD 

In both the main characters are transported to another world which is a sort of another dimension of the same world. There are a lot of girls in both and only two main guys. In both the characters have to fight in order to survive because they are attacked by monsters, and the main guys possess a great power. In both there´s a powerful white haired girl that is the source of the evil monsters and knights that attack them and also in both, that girl loved someone that was killed long time ago and that man is somehow connected to the main guy.  read more 

Both main character and the best friend transferred in to an alternate world. The main character became the good guy, while the best friend sided with the bad one. In the end they were ‘battling’ for what they believed…  

In both the main characters are transported to another world, where a war is about to begin between two clans. In both the priestesses have a main role in the stories. There´s also romance. Izumo has female harem, Harukanaru has male harem.  

First of all, some of the character design are quite similar and both have a similar concept in an powerful dormant force residing within the main character(s). Both are also more action based as well and being set in an outside realm. Although Utawarerumono overall, in my opinion, is better structured than Izumo, if you had a good time watching Utawarerumono, I think you will have a decent time watching Izumo.