Time to press E!
And go into Regulation E! The brand new regulation that will be used for the upcoming season of Ranked Battles for Scarlet & Violet.
Regulation E will run from October 1st to November 30th. This regulation will allow you to use any Pokemon in Scarlet & Violet including the Pokemon in The Teal Mask. That also includes any Pokemon transfer through Pokemon HOME. If you plan to go to any Regionals after October 1st then Regulation E will be used for those competitions.
Restricted Legendary Pokemon and Mythical Pokemon are still unable to be used in Ranked Battles.
Best of luck in your battles!