Is this a shadowstep bug or intended?
Shadowstep is a zero casting time skill, as are most teleports that I’m aware of, and therefore will not interrupt other actions. This is the same reason I can Steal while in the middle of my Cloak & Dagger attack animation. The effects of both Steal and CnD go off without a hitch.
It’s a lot like how a Mesmer can shatter while doing something else, or an Engineer can overdrive or blow up a turret while otherwise preoccupied. It’s not cheating, and I’d keep using it if I were you.
This works with Steal too. You don’t even have to look! Only useful against other Thieves, but if your Steal is off cooldown and you have no item already, you can hit Steal right after he teleports away and you will land your stomp on him.
I also use Steal vs. Guardians; first jump away from a Guardian who is down, wait for his AOE to knockback your friends, then Steal to get right on top of him and be the first one to stomp him.