You would probably have to go into further detail what is happening vs what you want to happen.
Out of the box UE4 offers physics actor replication. This already does what you said you wrote, position and velocity are shared from the Server and clients replicate this. There will be a choppy movement when the information from the server is unexpectedly different from what the client predicts. You will get desynchronization when physics actors are gonna get pushed around in one client/the server but is not replicated properly.
Are you replicating the events of the physics actors getting pushed around properly?