The Team Rocket Takeover has returned to Pokémon GO, and just like always, the Rocket Bosses like Giovanni and Sierra arrive with a new line-up of Shadow Pokémon for trainers to battle against. These bosses can have challenging teams, and players looking to beat them must plan ahead and strategize for the challenge.
https://screenrant.com/how-to-beat-sierra-pokemon-go-april-2023/