If there was Fairy types, i would've just called them either Nature, Myth or Fae Pokemon, basically they would be....well something of a special version of Steel, instead of being resistant to manmade types, but usually strong or weak against natural or supernatural types.
• grass, ground, water, dark, Fae = normal damage to and against • dragon, psychic = strong when being hit. • ghost, flying, bug = not effective against it. (ghosts are unexplained creatures, bugs and flying types lives in harmony but not strong.) • Fire, Ice, Poison = Weak against. (heat and cold are natural things, though poison kills nature) • Electric, Steel, Fighting = immune against. (fighting's argument is the same as flying, manmade structures can't stand in a forest and Electricity could be a different concept to Fae creatures) • Normal does has both regular damage and resistances to Fae.
Fae would probably be added to some older pokemon just to define them for balance sake of somesort, or to make some pokemon more/less desirable in battles.
RSN: Plucky9, Total: 2373 KoL: Plucky, currently a Avatar of Jarlsberg