(I've just got the game, so I don't have much. Bear with me, as I'll update this list as I get more to offer).
Looking for:
Swinub, Snow Coat, untrained.
Any Shiny
Any starter from 3rd, 2nd, and 1st gens.
Pokerus carrier, for Ev's.
Offering:
Palkia
Mesprit
Azelf
Uxie
Giratina
Rotom
Untrained Feebas
Untrained Vaporeon, Jolteon, Flareon
Eggs:
(can be hatched if you want a particular nature)
Turtwig Eggs
Chimchar Eggs
Piplup Eggs
Sheildon Eggs
Combee Eggs
Feebas Eggs
Eevee Eggs
Shinies:
Shiny Sandslash
Looking for:
Swinub, Snow Coat, untrained.
Any Shiny
Any starter from 3rd, 2nd, and 1st gens.
Pokerus carrier, for Ev's.
Offering:
Palkia
Mesprit
Azelf
Uxie
Giratina
Rotom
Untrained Feebas
Untrained Vaporeon, Jolteon, Flareon
Eggs:
(can be hatched if you want a particular nature)
Turtwig Eggs
Chimchar Eggs
Piplup Eggs
Sheildon Eggs
Combee Eggs
Feebas Eggs
Eevee Eggs
Shinies:
Shiny Sandslash