All the two emoji combinations are enumerated at https://github.com/UCYT5040/Google-Sticker-Mashup-Research https://github.com/UCYT5040/Google-Sticker-Mashup-Re

All the two emoji combinations are enumerated at https://github.com/UCYT5040/Google-Sticker-Mashup-Research https://github.com/UCYT5040/Google-Sticker-Mashup-Research. There is also info about the internal API Gboard uses on there.