the vWii version only work with USB, so if you currently have your emuNAND folder on SD you will have to move it to USB.
not all USB are compatible, there are some requirement (sector size, partition table, partition format, etc.)
If you want to setup Neek2o for the Wii, I wrote some guides :
https://gbatemp.net/threads/how-do-...properly-utilize-emunand.437521/#post-6592730
this one is the main guide, it links to 2 other guides : building neek or neek2o using modmii, and building neek or neek2o without modmii.
If you want a guide to build vWii neek (not neek2o) there is one in the WiiU hacking section, written by JoostinOnline.
You will not have channel autoboot from USBLoaderGX, but you'll benefit from the neek's better compatibility for some games, like Bonsai barber or Castlevania (or the other rebirth series), and all the N64 games.
auto-boot is a nice feature, but it's better to be able to play the game from neek than not find the illegal to share neek2o for vWii at all.