Movement sending (MMORPG)

How would I send the movements that one user makes to another user?

I wan't Symbol 67 to move to the position that user A makes on user Bs screen. And Symbol 67 on user As screen to move where user B moves. I am using Dpad movement:

Code:

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onClipEvent (enterFrame) {
    if (Key.isDown(Key.RIGHT)) {
        this._x += 5;
    }
    if (Key.isDown(Key.LEFT)) {
        this._x -= 5;
    }
    if (Key.isDown(Key.UP)) {
        this._y -= 5;
    }
    if (Key.isDown(Key.DOWN)) {
        this._y += 5;
    }
}

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