Guess 🍑 is kind of generic, after all, who doesn't have one?
The ⚧️ Transgender character is kind of an "all in one", but its meaning is more about gender than about the genitalia symbols it's made of.
The ☯️ yin yang is a representation of balance, among other things of the feminine-masculine.
As mentioned, the 🌺 kind of evocates genitals without specifying which ones, but it's rather associated with female ones.
In polyamory, there is 🦄 and 🐲, but they again refer to particular concepts that may not be what you wish to convey.
I don't think there is a single emoji unequivocally meaning "erogenous zone" without some gendered connotations. On the bright side, nothing is stopping you from using whichever emoji or combination you want. Sexuality is a conversation, it isn't a one-fits-all, and you are allowed to ask or offer further clarification.
When in doubt, 👄👅😏♥️... 🃏🌸