Are walking and standing mutually exclusive, and should they be?
I checked and found 27 pages with standing walking search and 81 pages with standing -walking. There certainly many of the 27 pages are images where one character is standing and another one walking. So generally it appears that it is thought that a walking character is not standing.
But for me it feels like a humanoid who is walking, is also at the same time standing (lest they are staggering badly). I'm not sure if there are exceptions with non-two-legged characters. I don't think walking should implicate standing necessarily. I guess a character can be walking in the air without then standing on ground...
In some images it can be difficult to say, whether a character is just standing in a walking position (one foot in front of another), which would be easier then to allow it to be judged for either both tags, or just standing. This post would then come up with search for standing.
The next question then is, of course, if the same applies to running?
Which way either, we should make a choice here and put it on the related wiki pages. Either "A walking/running character should not be tagged as standing", or "A walking/running character should typically be tagged as standing as well".