>>30311546>ResetThere are instant EV resetting drinks available from high tier shops in Festival Plaza, not sure which ones though. Unfortunately it's very grindy compared to Join Avenue as you can't simply upgrade shops, and the only real way to improvise it is to grind out that Battle Matchup mission online.
From Ula'Ula Island, you can find EV reducing berries. Poke Pelago offers many planting spots for them if you keep upgrading Isle Abeens.
>TrainingSimilar thing here, shops at their best can offer instant EV maxing drinks. Pelago offers passive EV training, which I think maxes out a single stat within 31 and a half hours (15 and a half with beans)?