After Ladybug/Marinette and Cat Noir/Adrien defeated Shadow Moth the Miraculouses were scattered around-for a reason that will go unnamed-except for the Ladybug and Black Cat. A new Ladybug and Cat Noir were chosen and now use their powers to defeat Mothia and Peacock before they find the Miraculouses. Also the occasional new hero who give their Miraculous back to Ladybug after the mission and only to be used when they're needed.

(Please don't judge my lore I am doing my best here)