Hi,
Currently, there is no direct support to model mecanum wheel drive In MATLAB. We do not have a motion model or waypoint follower that can be used for a holonomic drive.
You can use the transformtraj to interpolate between the waypoints to get intermediate states of robot, or use the unicycleKinematics to model the motion through the waypoints.
A reasonable workaround can be to consider holonomic motion as a UAV motion at a constant height. The dynamics in the case of constant height UAV motion will be the same as a Holonomic drive. Then UAVWaypointFollower can be used to follow the waypoints.
Hope this helps !!