Yokoyama Mitsuteru Sangokushi

Similarity: * both series are base on the Romance of the Three kingdoms. * They share the same historical setting, exploring the political and military conflicts during the Three kingdom period in ancient China. 

in both serie´s a lot of chinese influence has been taken from folklore, mystisyscm,and ofc, dragons that plays a huge role , either worshipping like in ROTK or showing the respectfull might in sohryuden, in asia it holds a near god like status! 

It seems to me the author of LoGH was inspired by the ancient Chinese story RoTK. In other words, LoGH is a space version of RoTK; both of the stories focus on political and war strategy rather than battle scenes. Oberstein is like reincarnation of Zhuge Liang.  

Both are based off of the same characters, but have completely different stories. 

Similarity: Based on Romance of the Three Kingdoms Tons of epic moments Similar character designs Different moments: Souten Kouro has better animation Souten Kouro tells story of Cao Cao, Sangokushi - about all characters of Romance