If you go back to the Aether Foundation trailer on Route 8, where you first spoke to Colress, you’ll find the eccentric scientist has returned. He’ll present you with a Douse Drive, Shock Drive, Burn Drive and Chill Drive.
These items can be given to the Mythical Pokémon Genesect to hold. Doing so will change the Type of its Techno Blast move to match the drive it’s holding, sort of similar to Arceus’s plates or Silvally’s memory drives. Unlike those items though, Genesect itself doesn’t change Type, so the drives merely improve its Type coverage.
After speaking to Wicke following the events of Episode RR, head to Secret Lab A in the Lab area. Secret Lab A is the first lab along the corridor, which Gladion was investigating during the story. Inside, you should find a female employee in the nearby corner.
Say “hi” to the employee and she’ll unload a bunch of items that power up Legendary or Mythical Pokémon: DNA Splicers for Kyurem, Prison Bottle for Hoopa and Soul Dew for Latios and Latias. With the exception of Hoopa, it’s possible to find these Pokémon via Ultra Warp Ride.