Genshin Impact 4.0 update hasn't been released yet, and the leaks for future versions have already started surfacing on the internet. They have revealed a new playable character named Emilie from Fontaine, who will be coming to the game in the future. As per HutaoLover77, she has multiple mentions in the voice lines of Lynette and Lyney and is Fontaine's Perfumer.
Genshin Impact 4.0 text map about Fontaine, which is leaked by HutaoLover77, says, "Otherwise, my friends and I often go to Cafe Lucerne. The smell of coffee is just too good — even better than Emilie's perfume."
Hutao Lover has also shared her concept art, and you can have a look at it below.
In terms of release date, element, weapon, and abilities, there is no information about them at the moment. However, we will update this page as we get more details about Emilie, so make sure to keep an eye on it.