Where did you find these images? You should provide a link back to where you (presumably) downloaded these images in every upload under the "source" heading.
So you want me to source some arbitrary person's Twitter who posted images from the game? I have never done this in the past and have waited for the cards to appear in the online compendiums in a day or two and it's never been a problem. If you REALLY think it's better to credit a non primary source / reposter alright, but I do not think that is even a shade of constructive.
Well, now that I can look at your source now that you've linked it, you've used a link to a Twitter sample. Howto:Twitter. Hence, yes, it is helpful. Sources help other users figure out whether there may be better sources for better versions of the same image. (And this image is terribly compressed with jpeg artifacts, which isn't rare when someone is reuploading twitter samples of something that was previously reuploaded onto Twitter after being a Twitter sample.)
Besides that, if these are all official artworks, it should be coming from official sources. If they don't get uploaded to official sources until a few days later, then waiting those few days is fine, especially since we're explicitly trying not to host more Twitter samples nowadays.
They may have originally come from the game itself, but that doesn't mean there hasn't been some bad compression from there to here. There's some really obvious jpeg artifacts, here, and I'm hardly one to be that notices these things, so if I'M the one noticing them, they're pretty glaring.
When WaifuFlagCrusher69 went and put sources to some of the other images that linked to a wiki, those wiki images also happened to have larger file sizes and less jpeg artifacts than the ones that were uploaded here on Danbooru, which is kind of the point being made, here...