Air carrier First Officer reported upon touchdown only one engine was able to get full reverse resulting in loss of directional control. The flight crew was able to regain control of the aircraft and taxi to the gate.

Narrative

Upon touchdown from stabilized visual approach; I was only able to get left engine into full reverse as wheel brakes applied. Aircraft developed significant left yaw after touchdown and initial deceleration. Control was regained by bringing throttles out of reverse and increasing right brake/pedal pressure. Captain assisted with braking and maintaining control and later noted the amount of right pedal required to maintain control. Reattempt to bring both throttles to full reverse was successful and aircraft decelerated and we exited via high speed turn off. Subsequent taxi was uneventful. Brake temp on left MLG was green and right MLG was at the green/orange line. Post flight walk around revealed left inboard tire had a flat spot. The tire was written up and reported to maintenance who changed the left inboard tire and brake.Cause: Suspect the the left inboard brake locked up upon touchdown which brought the nose left so quickly that would not have normally occurred with only one engine in reverse thrust.Suggestion: A stuck brake emergency at high speed needs to be conducted in the sim as part of initial and annual training requirements to prevent runway excursions.