Unspecified edition means that it could be any edition you receive correct? So, say I trade for (an example) a giant spider, but have not specified what version it is on my wishlist, and someone sends me any version they are good right?

That's the way I've always treated it. If they want a specific printing, they need to ask or select someone who has set that attribute.

Now for the separate topic of people not understanding Chronicles or the difference between Unlimited/Revised/4th, that's a whole other can of worms...

My advice is to always confirm details in trade chat if nothing is specified. If I don't care which edition, I'd just say "I don't care which edition the _____ is."

If I did have a preference, even if not specified in the wishlist, I'd just state, "I'm only interested in the M11 version," or something similar.

Communicating helps prevent misunderstandings.