That depends on how different it’s water is from your tank. The main factors of shock come from temperature, pH and dKH differences. If its within a few degrees temp, 0.5-1 dKH and 0.5 pH difference, there shouldn’t be risk of shock.
To be honest I don’t think I’ve ever drip acclimated or even checked the bag water of any of our urchins, I’ve yet to lose one that wasn’t already half dead upon arrival or to an unrelated tank swing later on. But we also keep our tank parameters as close to our supplier’s as possible to prevent problems.
Some species will be more sensitive than others, I’ve had long spines, collector’s (normal and dwarf species), Halloween’s and tuxedo’s, multiple species of each type.
