Kleopatra has "Lookup Key" which searches the keyservers. It also does an implicit "--locate-key" (WKD Search) when recipients are entered.

It should combine WKD Lookup with the Keyserver Lookup feature.

I think the best implementation might be the following:

1. When searching for something that looks like a mailbox do a --locate-key with WKD enabled.
   1. If no key is found, do a keyserver search as we do now.
   2. If a key is found, show that key.
      1. Show an additional button "Search on Keyservers" so that advanced users still have the option to skip WKD and we don't have feature loss. (E.g. this could be important of X509 keyservers)