The Major difference between Motion Graphics and Visual Effects is
Motion Graphics is an animated graphic design, which is created using digital footage creating an illusion of motion or rotation. This footage is usually combined with audio for creating a multimedia effect.
Visual Effects combines existing footage with computer-generated imagery to create realistic scenes. Visual graphics can be used to illustrate specific relationship and the pattern of data in the most readable format, such as bar, pie and line charts.
We generally use the phrases VFX for visual effects and Animation for motion graphics.