Gengar - 3* Gengar is able to cheat the evolution process that hinders many stage 2 decks. Placing damage on one's own Pokémon (that isn't part of an attack) is not a common thing nor is it usually a good thing (Single Strike Decks are one of the exceptions). Placing damage counters can setup Pokémon such as Machamp Vmax, Zoroark V* and/or take advantage of Damage Pomp.
R. Gardevoir - 4-5* Gardevoir will see play and probably more so than Hawlucha (as there are only a handful of viable Vmax decks left and most of them are reliant on Inteleon/Cinccino). Goodra V*, Duraludon Vmax, Arceus V*, or any other passive wall decks that can take full advantage of Gardevoir and/or Lake Acuity.
H Zoroark - 2/3* Not a great card by any means, but any form of insta-kill (or any form of it) must be respected, to a degree. Butterfree (until Rotation), Muk (BRS), and H. Zoroark with a combinaton Spikemuth/Temple of Sinnoh, Tool Jammer, and Crushing Hammer/Flannery could make a nasty deck combo. (*Note: Zoroark will probably be out near time of rotation, so this idea with Zoroark might not be able to happen in Standard, but maybe there will be a new insta-poison ability/item card by then (or a similar idea/strategy)).
H Zoroark V & V* - 3*/5* Is one of the best offensive V* Pokémon revealed so far, and there were plenty of candidates for this label. Between Lucario (BRS), Gengar (above), and Damage Pomp (below) to name a few options for Zoroark V*. 300 damage (Choice Belt for 330) so long as all your Pokémon have a damage counter is great, plus all the other numbers of Zoroark work wonderfully, so long as there are at least 4 of one's Pokémon with damage counters. *Note: unless Rare Candy has a reprint, Inteleon (including Quick Shooter) will disappear, but you will still need a check for Urshifu (RS, still one of the best decks going into rotation, with/without Inteleon/Cinccino) as it only really needs 2 turns to end Zoroark.
H Goodra V & V* - 3*/4+* The best wall or tank potential, so far of the V* Pokémon, and between its own attack, Gardevoir (above), and Lake Acuity/Crystal Cave, plus any other disruptive/control cards that we end up with, Goodra will see play. The only thing that might be holding Goodra back is the attack cost, but once Goodra is paid for, getting rid of Goodra won't be a simple task with a potential effective HP of 410 (between its attack, Gardevoir, and Lake Acuity).
Damage Pomp - 4* A weaker version than its predecessor, Damage Mover. Unlike Damage mover, there are plenty of Pokémon now that can advantage of this effect this time. Gengar (above), Lucario (BRT), and Houndoom (BST) can all supply damage counters for Damage Pomp to move to a more appropriate target. Almost any deck as well as many Pokémon that benefit from Damage Pomp: Mew (if there is room, moving extra damage on Mew or Genesect to Oricorio, Latias, or other Genesect to spread out the damage), Primeape (SS), Zoroark V*, Machamp Vmax, Radiant Heatran now becomes viable, and of course moving damage to support Pokémon and away from the main aggressor is almost always good.
Lake Acuity - 4* Enabling Pokémon with Water or Fighting energy to ignore 20 damage. This includes Goodra V*, Duraludon Vmax, all Fighting decks (including Single Strike), and Water decks (i.e. Palkia V* and Suicune V)
Iscan - 3* A decent draw option for using in Hisuian decks that provides reliable draw, when one can't be reckless with Professor's Research while Marnie moves to Expanded. *Note: almost all the Hisuian Pokémon revealed so far are pretty good and will/could see play.
Arezu - 2* (4* in niche decks) I can't see this seeing play outside specific decks, like Zoroark (EVS). Stage 2 decks will disappear from viability (unless they can build themselves up like Torterra) until there is a Rare Candy reprint or equivalent (Vigor Shake is only viable turn 1 or niche decks)
I have been impressed with Pokémon lately, mainly due to fact that they are listening, somewhat. Since Evolution Skies (maybe a little before), Stage 1 and Stage 2 decks have gotten much better/stronger, and if Rare Candy survives rotation or returns in Generation 9, stage 2 decks will live on.