I mean, this shit usually happens after the game comes out and everything settled. This is the first time I've seen otherwise.
You should see previous entries of the series. It was very similar. This made me look at other series how slow those people are really. Like game need a week or two for any fanart to come out but in Touhou case it's just hour after releasing a cover of CD for DEMO. This community is truly something else.
Also, there is missing copyright for "Willy Beast and Weakest Creature" since it was made for this game.
It's not a reference to the game in any way, shape or form, except for Urumi's presence. For the purposes of tagging the various Touhou games on Danbooru, there needs to be more than that in order for the game to be tagged, unless it's made quick enough after the game's release to go into the Wow That Was Fast pool.
Otherwise, all 39 thousand images of Remilia would have to have the EOSD tag added.