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Wish and Teleport are incompatible on chansey since they are exclusive to gen1/LGPE and gen3 respectively, so unless the DLC adds a teleport move tutor Chansey can use, it is not running that anytime soon.
Considering your slashes give the option to not even use grass STAB, I doubt you'd want overgrow. Even with Giga drain, idk what sort of low hp overgrow calcs you'd want to land with it, so you're probably better off with Chlorophyll just in case you run into a sun team.
I think you meant to say switch-ins, since the only other 100% safe switch-in I can think of is Avalugg. There's a lot of scarfers besides Jirachi that can revenge kill Kyurem B, some of which, namely Hydreigon, were used and viable before kyub dropped. I've personally been using scarf Terrakion...
I'm pretty sure they are compatible on cart since there's no reason the new daycare mechanics wouldn't apply to transferred mons. Showdown simply hasn't removed egg move transfer move incompatibilities yet.
Well this is just straight up wrong. Teleport is an LGPE transfer move and its confirmed that LGPE transfers do not have hidden abilities. I also tried to pair it with Wish, and it says those are incompatible despite Wish being a gen 8 egg move that can be given to a teleport clef via the new...
Unreleased mons are just that, unreleased. Which is to say there's no way to legitimately obtain them in game yet. Illegal mons are either banned or impossible (conflict between moves and/or abilities, or it simply knows moves it shouldn't).
Tapu Bulu @ Choice Band
Ability: Grassy Surge
EVs: 84 HP / 248 Atk / 176 Spe
Adamant Nature
- Wood Hammer
- Horn Leech
- Superpower
- Stone Edge
Check. While Bulu doesn't exactly come out of this matchup unscathed, it doesn't get OHKO'd either, and absolutely annihilates Gliscor with wood...
Tyranitar @ Assault Vest
Ability: Sand Stream
EVs: 224 HP / 32 Atk / 252 SpD
Careful Nature
- Rock Slide
- Crunch
- Pursuit
- Earthquake
This beast has such a ridiculous amount of sp. def that it can easily out-tank both those mons, especially without a Z crystal on volc. You'll find rock slide...
Tapu Lele @ Choice Specs
Ability: Psychic Surge
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Psychic
- Moonblast
- Psyshock
- Hidden Power Fire
While lele will have issues switching in against lando, once its in it OHKOs the entire core with just Psychic.
252 SpA Choice Specs Tapu Lele...
Lopunny @ Lopunnite
Ability: Limber
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Return
- High Jump Kick
- Fake Out
- Ice Punch / Quick attack / Power up punch
Boasting a faster fake out and the ability to outspeed Tapu Koko, lopunny here becomes a huge obstacle once it actually manages to get...