It’s not that simple for two reasons:
- different platforms support new released emojis at different speed, so you could have user A on platform 1, creating a post using an emoji available on this platform, which will then be seen by user B on platform 2 which doesn’t support yet the latest emojis released few weeks ago => tofu box (in the world of fonts, “tofu” is a blank rectangular box that appears when a character cannot be displayed).
- custom emojis. Discourse supports custom emojis which are not mapped to a character and are just images.
No unless you want to change it