Hide frequently used Memojis from Emoji keyboard in iOS 13

I just upgraded my iPhone to iOS 13 and I noticed that, while composing a message, when switching to the "Emoji" keyboard (that now can be accessed through an apposite button), it shows, on the very left hand side of the screen, my 8 most frequently used Memoji. This is very annoying to me, since I almost never use Memoji and I'd like just Emojis to be shown. Does someone know how to hide Memojis from the Emoji keyboard?