Comparerd to knights, there are too weak. Over 5 crossbow and beat knight(full up)
But why do we think they are OP?
Because they are stack from Feudal ages
If you train more than 20 archer from Feudal ages,
It is very reasonable your crossbowmen beat knights who appear 2 by 2 (even if you have 2 stable)
I have never thought this games archer-line is OP
If both players start Castle same, archers never have chances to beat knights.