In Season 3 of the anime King meets Rou, and he confuses with Ban because they look almost identical. The Nanatsu no Taizai wikia states:
Rou looks nearly identical to Ban, except with a neater haircut and a fringe that reaches his right eye.
Later Rou meets Meliodas and he greets him with a "handshake" identical to the one Meliodas does with Ban. But when you are about to think Ban is the reincarnation of Rou, the story shows Rou reincarnated in Oslo.
How are all their similarities possible then?
Are Rou and Ban related in any way or their similarities are just pure coincidence?