The Alola games are the only ones in which a significant number of opposing trainers outside the designated postgame battle facility have any EVs at all (no main-series game prior to Sun and Moon had even a single such trainer). Most important trainers like trial captains and route bosses will have their EVs maxed out in two designated stats, and the totem bosses (which use trainer AI) also have EVs which are always focused entirely in bulk.
EVs were made less of a point of emphasis in Sword and Shield, but a couple trainers still have them, including Piers's Obstagoon (which uses HP EVs to boost that stat and make up for at least part of not having access to dynamax in that gym), and the Eviolite tutorial trainer who demonstrates the buffed defenses of both Eviolite and EVs on their Dottler before they give the item to you.
