Seeing as the pose directly references Jack-O’ (the vast majority of the time, at least), and that I’ve seen a good number of jack-o'_crouch_pose posts without other GG-related content tagged with guilty_gear, it would make sense to me to have the former tag implicate the latter. But I don’t know much about tagging, so I thought I’d leave this question here before making the change.

Please lemme know what you think.

IMO, no. Looking at images with the jack-o'_crouch_pose doesn't seem to have any indication of being related to Guilty Gear. And as I mentioned in topic #30508, it's very similar to a couple pre-existing yoga pose tags and could be easily taken as simply another pose. The only thing with any relation to Guilty Gear is the name (though even then, it depends on you knowing the character; I thought it was referencing something about Jack-O'-Lanterns when I first saw the tag).

Are we going to start calling shadow boxing "taokaka_taunt_pose" as well?

Going by TWYS, unless we see something that obviously depicts Guilty Gear, such as costuming, a scenario from the media, or a character, then a mere pose that frankly could be seen as an unrelated pose won't be specific enough to warrant the tag. It's likely a number of those hack-o'_couch_pose posts are mistagged.

Even though the wiki page for just_right suggests to also tag pacha_(the_emperor's_new_groove) as the character who originated the pose, there is no implication set up for that. Pacha should, however, implicate the_emperor's_new_groove (though he currently doesn’t), but that would create the problem of adding that tag to every post that features that pose, though most or all of them will have no relation to The Emperor’s New Groove beyond that pose.

We have the same situation here. Does the pose itself warrant tagging the character jack-o'_valentine? That should also imply Guilty_Gear. But as others have said, the pose alone may not be relevant enough to add the game tag. Whatever happens, we ought to give the same treatment to both these cases, as well as any other scenarios involving a meme inspired by a particular character. Personally, I’d like to remove the Pacha tag from all the just_right images unless they actually include the character. Currently, trying to search for art depicting Pacha (not that I really expect many people to, seeing as he’s a human, but still) results in the very few images depicting him being buried in a bunch of Just Right posts where the character himself is not actually seen. If the character is also cosplaying as him, then I could see it. But otherwise, that does not seem to be the way to handle character tags.

Edit: think mark think! is also very frequently tagged along with invincible_(comics), which is another similar issue.