For example I did the following:
I brought a leafeon and used leech seed
Then a yamask or runerigus and swapped the abilities
Then a sturdy Pokémon that used a physical move
Then sent out a level 1 woobat with a focus sash
Used skill swap
Then speed swap
Will speed swap fail?
Speed swap or Skill Swap would fail? Actually, it doesn't matter. No, it shouldn't fail. There is nothing in the description that would indicate that in would fail on a Pokémon a higher level than you. I'm curious to try it but it should work like it would on a Pokémon the same level as yours. OHKO moves will fail if the target is 30 levels or higher than the user, but those are the only moves I am aware of that will change accuracy depending on the user and target's level. Hope this helped!!!