The implementation is fairly simple, you upload PNG files for the logo, a border color in hex code digits (#00000), and the images for the trading cards, badges, and backgrounds.
The one thing I will say is, they make the files be a specific size, to the pixel. So that could be a source of frustration. As per the slowness, Steam did recently update their policy regarding actually putting cards LIVE, you need to have a fair amount of people playing, and buying your game (ToL = Check on those two points, if 1k people playing isn’t enough, then wew.) because ‘fake’ games were being put on the store for the sole purpose of having cards, so that is true indeed.
That being said, it should be fairly simple if you do a decent amount of image resizing in Photoshop, but then again- then the images (may) look weird, and for emojis just take the ones from the Discord- backgrounds? Use the winning screens! I will say, however, the developers do appreciate art in the game, so I doubt they’ll do the cards half-ass (as once they’re live, pretty sure you can’t edit them…) such as simply resizing and possibly unproportional photos, that would be my guess as to the wait.
But you know what they say, patience is a virtue, and with patience comes quality.