*Infinite Eevee glitch.
*Make your own items glitch.
*Trainer-Fly (called fifth in Japan).
*Yami Shop glitch and Pokéflute encounter.
*Defense experience byte 2-># of items.
*Item underflow glitch.
*Fossil conversion glitch.
*Text pointer manipulation? (unconfirmed).
*Glitch Cities with useful screen data.
*Super Glitch for over 6 Pokémon? (unconfirmed)
*ZZAZZ glitch # of items expansion? (unconfirmed).
*Item duplication via Missingno.
*Skip to level 100 select glitch.
All can be found with Google, some from my channel ChickasaurusGL, some are more well known.
Some glitches listed may obsolete another.
Magikarp into Mew is not included, because it probably won't get registered in the Pokédex.
I suspect text pointer manipulation would be harder on Red/Green, due to the first byte being an item quantity instead of an item.
For CoolTrainer, the memory layout, etc. may mean the location where you need your 50/species byte would be different. But CoolTrainer is unconfirmed other than the basic yields by opening a battle screen (Missingno. and Pikachu IIRC).
Pokémon you can get with the glitches:
Trainer-Fly: Lots of things, everything with a Ditto.
Fossil conversion glitch: Everything.
Pokéflute encounter: 32 different Pokémon confirmed, but more may be possible with Glitch Cities.
CoolTrainer: Likely to be quite a few.
Text pointer manipulation: Unconfirmed. What is allowed to be in an item ball, so e.g. Mew (Boulder Badge) probably doesn't count.
Any specific questions? I'm happy to answer them. :)