Red Controller:

North:
/summon armor_stand ~0.23 ~-2.51 ~ {NoGravity:1b,Pose:{Head:[0f,270f,0f]}}

East:
/summon armor_stand ~0 ~-2.51 ~0.23 {NoGravity:1b,Pose:{Head:[0f,0f,0f]}}

South:
/summon armor_stand ~-0.23 ~-2.51 ~ {NoGravity:1b,Pose:{Head:[0f,90f,0f]}}

West:
/summon armor_stand ~0 ~-2.51 ~-0.23 {NoGravity:1b,Pose:{Head:[0f,180f,0f]}}