Playing around with Catodon and really enjoying it. I just thought it was really interesting to note that emoji reactions do federate. Although for some reason Piefed shows 2 when there's only 1.
For those unfamiliar "'keys" are the many Misskey forks. i.e. Catodon, Iceshrimp, Sharkey, etc.
I assume any non-standard emojis will be instance-specific.
:catodon:is all the server receives, and then matches it with a known local emoji image. If one doesn't exist, you just get text. It seems the :neocat_glasses: is loaded onto piefed.social@artyom@piefed.social @Lojcs@piefed.social that's probably because piefed doesn't support custom emoji (or at least custom emoji that are compatible with misskey and akkoma, like we do).
Yes this is pretty rocky in PieFed. Since making an initial implementation of emoji reactions I haven't come back for another pass to clean it up based on the bugs that have shown up in production.
PieFed makes a daily request to /api/v3/site on each Lemmy instance, to get a list of admins and emoji. I've just checked and found that catodon.rocks has the same endpoint so that looks like something to try.