Too late I read the title, -1
Scenario:
Buy a poke, use in PvP, realize it's awful or you want a different nature, abi, etc. SELL TIME
Scenario 2:
Mid season - guildmate A finished getting ladder, doesn't need pokes he used anymore, lends a couple to guildmate B so that he can pvp with his team/test a new one
This is already allowed in normal ranked pvp though that's the thing, I won't lie I've asked for pokes from guildmates and had them lend me pokes to try out on teams and use them for a while, learned some new teams, new styles, etc. Thing is, there's no "Between season time" which means you're basically asking, if someone pvped once with a poke, that they wait at max an entire month to be able to sell that poke for pvp.
Refresh my memory I'm not a ladder player, it was on showdown previously correct?