There is also https://emojito.meme/ that let's people make packs you can subscribe to. nostr:nprofile1qqs8a474cw4lqmapcq8hr7res4nknar2ey34fsffk0k42cjsdyn7yqqpz9mhxue69uhkummnw3ezuamfdejj7qgwwaehxw309ahx7uewd3hkctcpz9mhxue69uhkummnw3ezumrpdejz78wwyvs has made some good ones. It's focused on reactions, but they can also be used as stickers in some clients.
Discussion
Is there enough variety for a gif keyboard ?
It has a pretty good selection already, and if it were included in more clients it would be even better. Anyone can curate packs, and get zapped for them. If stickers on signal are anything to go by this could work.