This is probably obvious, but my opponents havent been doing it against me so here goes:
Wanderers are super easy to bleed with midrange decks (SY, SK etc). If I know I am playing against sunset wanderers, I put extra effort into winning round one that I wouldnt do against a normal deck, sacrificing a few mid tier provision cards to do so.
Going into round 2, you should know where Wanders are in your opponents hand, so just play junk until it comes out. I have had opponents win round 2 by 35 points. Obviously you'll have to go down a card into round3 – which is okay – because you should be up big in provisions remaining in deck.
This wont work with every deck because you need thinning and control your draws a bit to make it work. Also, this probably only works because people are misplaying in an attempt to keep wanders in hand for round 3. Ive had tactical decision opponents throw away the leader charge in round 2 to prevent wanders from coming out.