A body is acted upon by two unequal forces acting in opposite directions, but not along the same straight line. The effect is that the body will experience:

Let the two unequal forces be ${\vec{F}}_1$ and ${\vec{F}}_2$ acting in opposite directions.
1. Translational Motion: Because the forces are unequal in magnitude ($F_1\ne F_2$), the net external force acting on the body is non-zero:

$${\vec{F}}_{\text{net}}={\vec{F}}_1+{\vec{F}}_2\ne 0$$

A non-zero net force causes linear acceleration, leading to translational motion.
2. Rotational Motion: Since these forces do not act along the same line of action, they create a separation distance between their lines of action. This configuration produces a non-zero net external torque (${\vec{\tau }}_{\text{net}}\ne 0$) about the center of mass. This net torque induces rotational acceleration, causing rotational motion.

Therefore, the body will experience both rotational and translational motion.