To the extent you define wok hei as inviting the flame into the vessel to flash-fire the vaporized oils, I do this with regular frying pans, as long as they have fairly steep sides so the food won’t tumble out with the pan tilted, as easily (if not more easily) as with my wok.
The “if not more easily” comment is because the lower side height on these pans makes it easier to tip and get the flame to come inside using the burners I have available. They’re not exactly weak (18K & 15K front stove burners, 12K outside on the grill’s side burner) but they’re not the blast torches you see in commercial Chinese cookery.
(Caveat - see my thread on how badly gunked up my exhaust fan got.)
Edit - but now in reading further through the thread, I see your comment that the flash-flaming of the vaporized oils is only part of the story. And I have not tried this with a CS pan specifically because the sides are sloped enough I’m afraid the food would slide out. I’ve only done it with stainless and hard anodized aluminum pans. But I think my cast iron would fit all criteria. I’ll try one of them next time.
