Hello ! My coworker appears to have issue with export. Indeed, it creates this kind of pixelated outline all around the emote. Seems to be a question of anti aliasing. It seems that it started after the last adobe updates.
1. I use a PNG (as usual) 2. I use puppet tools to animate it in AE 3. I export it as a .mov. The I import it into Photoshop and export it again as a gif (this is the right method to create animated emote for Twitch)