I have tried to compile of list of pokemons (Emerald, Gen III) that are just placeholders. They could be replaced with Later gen pokemons or Variants to make the hack interesting, enjoyable and memorable! However, I would like to acknowledge that its just my opinion and I am sorry if I offend someone. Here is the list-
Poochyena, Mightyena, Zigzagoon, Linoone, Wurmple, Silcoon, Beautifly, Cascoon, Dustox, Surskit, Masquerain, Nosepass, Plusle, Minun, Volbeat, Illumise, Gulpin, Swalot, Carvanha, Spinda, Solrock, Lunatone, Lileep, Cradily, Chimecho, Clamperl, Huntail, Gorebyss, Relicanth, Luvdisc, Kecleon. 🙂