How to create this outline / stroke animation?

I also think that you can experience a little with the Echo effect, from a small text to the same huge text and playing with the number of repetitions.

Long and short: It probably doesn't morph at all. What you see is pretty much the default result you get with the Radio Waves effect, where sharp corners in teh source shape will eventually overlap and be optimized away by the underlying vector calculations. Sure, there could be other things at play, including elaborate mask blending/ morphs, but without any info on the actual source project nobody can answer that. In any case, I really think it's much more trivial and indeed boils down to using the Radio Waves effect.

Mylenium