>>33039820The whole perfume thing is just from the anime, and the anime fucked up like every gym leaders character, so I wouldn't pay it much mind.
Though "Erika's Perfume" is a card in the TCG (which uses her game design) and she likes the smell of flowers and stuff, so she probably still uses some, but it's kinda up to your own headcanon.
What's important is that she is very sleepy and does nice flower arrangements.