Effect of Fuselage and Fin Side Force
As the aircraft touches down, the side force created by the crosswind component on  the fuselage and fin tends to make the aircraft skid sideways (downwind) off the centerline, as illustrated by Figure 6.

Effect of Thrust Reversers
When selecting reverse thrust with some crab angle, the reverse thrust results into two force components, as illustrated by Figure 6:
.  
A stopping force aligned along the aircraft direction of travel (runway centerline), and

.  
A side force, perpendicular to the runway centerline, which further increases the tendency to skid sideways.

 
Crosswind
 
component
 
 
 
 Reverse cancelled and
Touchdown Aircraft skidding  Reverse thrust
brakes released

with partial sideways tendancy
and pedal braking decrab increased by reverse Directional control and reapplied thrust side force
centerline regained
Figure 6
Directional Control during Crosswind Landing
Flight Operations Briefing Notes
Crosswind Landings
The thrust reverser effect decreases with decreasing airspeed.
As airspeed decreases, the rudder efficiency decreases and is further affected by the airflow disruption created in the wake of the engine reverse flow, possibly resulting in difficulties to maintain directional control.

Handling Techniques to Maintain / Regain Directional Control
The higher the wheel/tire braking force, the lower the tire-cornering force; therefore, if the aircraft tends to skid sideways, releasing the brakes (i.e., by taking over from the autobrake) increases the tire-cornering and contributes to maintaining or regaining directional control (Figure 6).
Selecting reverse idle cancels the effects of reverse thrust (i.e., the side force and rudder airflow disruption) and, thus, further assists in regaining directional control.
　
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