Can you modify the state(pose/velocity/acceleration) of a model from a world plugin

edit

So I want to globally control and observe the interactions of all objects in my environment. The obvious way to do this seems to be through the world plugin. However setting parameters like linear velocity seems to have no effect on the simulation. I'm curious if gazebo is internally blocking modifications of models through the world plugin or if there is a particular setting that needs to be modified to allow this to occur. Thank you

So this here's a quick simplified snippet showing as to what I'm trying to do and how:

Let me know if there is more info you would like

void World_Plugin::Load(physics::WorldPtr _parent, sdf::ElementPtr _sdf){
   this->world = _parent;
   this->updateConnection = event::Events::ConnectWorldUpdateBegin(boost::bind(&Quasistatic_World_Plugin::OnUpdate, this, _1));

 }

 //pusher vel is just some velocity
 //pusher is a modelPtr I've extracted from the world
 void World_Plugin::OnUpdate(const common::UpdateInfo & /*_info*/){
      this->pusher->SetLinearVel(math::Vector3(pusher_vel[0],pusher_vel[1], pusher_vel[2]));
 }

World File

 <?xml version="1.0"?>
 <sdf version="1.4">
  <world name="blank plane">
    <plugin name = "quasistatic_world" filename="libquasistatic_plugin.so"/>
     <include>
      <uri>model://ground_plane</uri>
     </include>
 </world>
</sdf>

The model is added in the world plugin and looks something like this (simple box for now):

<sdf version="1.4">
  <model name="pusher_box">
    <pose>0 0 0.5 0 0 0</pose>
      <static>true</static>
     <link name="link">
       <collision name="box_collision">
        <geometry>
      <box>
        <size>1 1 1</size>
      </box>
       </geometry>
      </collision>
     <visual name="visual">
      <geometry>
   <box>
    <size>1 1 1</size>
   </box>
      </geometry>
    </visual>
   </link>
   </model>
  </sdf>