Pokemon Trading Has Been Tested On Nintendo Switch Online's Game Boy Emulator

Pokemon Gen 1 to 3 games haven
Pokemon Gen 1 to 3 games haven't officially made it onto NSO yet, but a programmer demonstrated that trading should work flawlessly.

LuigiBlood's Blog — What's the deal with the GB/GBA Emulator Leak?

Switch, SUBS] Game Boy Games Added to Nintendo Switch Online, Game Boy Advance Games Added to Expansion Pack @ Nintendo eShop - OzBargain

Nintendo Switch Online Game Boy emulator reportedly leaked

Looks Like Pokémon Trading Already Works On Switch Online's GB & GBA Emulator : r/nintendo

Is Nintendo Switch Online on the verge of receiving GBA titles? Recent reports would suggest so

Nintendo Switch Online: GoldenEye 007 Joins N64 Retro Library - CNET

Official Nintendo GBA emulator for Switch Online leaks

An official Game Boy Advance Emulator could be coming to Nintendo Switch

Report: Nintendo's Bringing Game Boy Games to Switch

Nintendo Direct reveals Gameboy Colors' Pokemon Trading Card Game Re-Release! : r/pokemon

KoopaTV: Pokémon Stadium on Nintendo Switch Online is a Reminder on Generation 1's Problems

Game Boy and Game Boy Advance games are coming to Nintendo Switch Online today - The Verge

Nintendo Switch Online - Every NES, SNES, N64, Sega Genesis, Game Boy, And GBA Game Available

Pokémon Trading Card Game, Stadium 2 Joining Nintendo Switch Online Library - IGN