I'm the author of d3-graphviz so you probably shouldn't believe a word I say ;-)

d3-graphviz is based on the Viz.js port of Graphviz and does animated transitions between graphs. See e.g. this demo: https://bl.ocks.org/magjac/4acffdb3afbc4f71b448a210b5060bca

Since d3-graphviz is based on Viz.js it can can do everything that Viz.js can do. Also, it adds the following features:

    Animated transition of one graph into another
    Edge path tweening
    Node shape tweening
    Fade-in and fade-out of entering and exiting nodes and edges
    Animated growth of entering edges
    Panning & zooming of the generated graph

Extensive docs at: https://github.com/magjac/d3-graphviz

Any feedback is welcome.