When picking her yourself she's quite useful against Cleavers, since you'll take the first turn anyways and slow down all their openers to base speed if your Harsetti is base speed as well. If you go against her and still wanna cleave her, Zio and Ml Roana are very useful since Zio will still take first turn, Roana goes afterwards and you can clean up with units like Jack-o or Summer iseria.