Yes.
The leader-board plugin didn’t exist when I did this and I haven’t done much (anything?) with it.
https://meta.discourse.org/tag/sql-triggered-badge
If the badge thing works for you, then a plugin (or perhaps something that calls the api?) that would automate creating the badge with the associated SQL would be a good idea.
If it’s a daily one, then there could be some way to make the badge SQL grant a badge for yesterday; or just have a single badge that can be awarded multiple times and grant a badge every day that they post the emoji.