Lorelei
Elite Four in Kanto.
About
Lorelei is the first of the Elite Four at the Pokémon League. Her team is mostly Water and Ice type, so Electric moves hit most of it hard, and her strongest are a level 54 Jynx and Lapras.
Elite Four battle
Rematches
These teams are in the game data, but no battle uses them: rematches are not in the game yet.
DewgongLv 64Ice Beam, Surf, Signal Beam, Double Team
CloysterLv 63Ice Beam, Surf, Supersonic, Rain Dance
PiloswineLv 63Blizzard, Earthquake, Double-Edge, Rock Slide
JynxLv 66Ice Beam, Psychic, Lovely Kiss, Attract
LaprasLv 66Holds 
Cheri BerryIce Beam, Surf, Psychic, Thunder
As of v0.75.0 · engine 22ba612f