These stickers are customizable emojis that use machine learning to turn a selfie of you into an emoji. From there you can further customize it if you’d like. Then you can use them in styles like bolt, sweet and emoji (as seen in the above image).
There are plenty of emojis to choose from once you’ve made your own. The feature is now rolling out for Gboard for both iOS and Android in all countries where it’s available. Check out the sticker section of the keyboard to make your own!