Wll, I have two illegal Pokémon (that they are a Celebi and a Melloeta shinies), so, If I don’t send them in online battle, I’ll be safe? Or they can ban me anyway?

Welp, I have two illegal Pokémon (Celebi and Meloetta Shinies) gotten from trades, cause I don’t hack... So, If I don’t send them in online battles, I’ll be safe? Or they can ban me even if I have that Pokémon in my boxes?