Opiniatrety

I think part of the issue here is that "trade" is a verb that mostly takes inanimate (or at least non-human) objects, while "want" is a verb that requires an animate subject. The concept of trading people in a sports context is the main area where the two intersect, so uses of the two verbs in combination are going to be pretty rare to start with. Since verb + present participle is a relatively uncommon (though grammatical) construction in most English dialects, particularly in combination with "want," I'm not surprised that "wants trading" is unattested.

Actually, come to think of it, "want" + present participle doesn't seem very common at all. It may just not pattern the same way as "need."

Here are some references on this feature, in case you're interested. I don't know if they mention "wants traded." I bet all of the people who used this are from PA and the middle-midwest. Wants x-ed, needs x-ed, and likes x-ed come from the English of the Scots-Irish who were the original settlers of this area.

Murray, Thomas E., Timothy C. Frazer, and Beth Lee Simon. 1996. need + past participle in American English. American Speech 71:255-271.

Murray, T. E. and B.L Simon (1999). "Want + Past Participle in American English." American Speech 74(2): 140-164.

Murray, T. E. , and B. L. Simon.(2002). "At the intersection of regional and social dialects: the case of like + past participle in American English." American Speech 77(1): 32-69.

I think it's really just a problem with "want".
*The car wants washing. *The car wants fixing.
Can you say these? I cannot. But replace "want" with "need" and it's ok.

Good citations! (See link).

See link.

Eep.

I'm not quite sure that I'd asterisk those sentences. "Wants fixing" does occur for, roughly, "needs to be fixed"; note that literally the car and most other examples of "wants fixing" can't want anything. Though there is "the person wants fixing" here , where 'wants' is literal. Searching reveals that "wants a spanking," "wants spanking," "wants a beating," "wants beating" also occur in our relevant form.

Which reminds me, about the link again, I sure hope no one's ever using my search history against me in court. "It was a linguistic formulation, judge! I swear!"

Anyway, note that the latter examples all could have 'a' inserted, but "wants fixing" couldn't. All of these also strike me as British or at least not American; the "wants fixing" I linked to above is from a Pakistani bulletin board, and check out "wants smacking" here. (Oddly, the only relevant "wants smacking" I could find; I looked for it before "spanking" and "beating." In some occurences of "wants spanking" 'wants' means wants, not needs.)

I would asterisk those sentences for my own idiolect, and I'm pretty sure they're similarly ungrammatical for most American dialects (as you note). In any case, I do think AN's right that the issue here is "want" rather than the syntax.

And "needs trading" does have some relevant sports-related Google hits, though I'm pretty sure I wouldn't say it.

Nonsentient beings: The noun "want" used to mean "need," "poverty," as in "freedom from want." "Wants" in "wants fixing" seems to be used in that sense.

Sentient beings: It's good Pittsburghese to say "the baby wants down" (from a highchair) or "the cat wants out." I think "wants out" is much more widespread.