Thats the ethos behind this Oricorio and Tapu Koko deck, which lets you safely deal damage with Tapu Koko and, thanks to its Volt Switch attack, switch out to Oricorio for the next turn, negating all damage from opposing Pokmon ex cards
GTS Distribution is the one most often cited as the largest, alongside others such as Southern Hobby Supply
so more generally, are creatures considered attacking immediately when they are declared attackers, do their triggers need to resolve first (step change), or something else
Forget about Standard, I would be surprised if this wasn't playable in Modern - at least as a sideboard option for dealing with artifact/enchantment heavy decks
There's a reason the old adage is "Bolt the Bird" rather than "Pacify the Elf." On top of this are more layers, usually also downsides: PacifismPacifism is vulnerable to a DisenchantDisenchant effect drawn at any point during the game, the creature's controller can bounce it back to their hand, and they can still use it to power some spells like Rabid BiteRabid Bite, or to sacrifice to cards like Village RitesVillage Rites