Hello, probably a week ago I spoke to someone from the team on Quin’s stream about this, sorry it took so long to post!
Anyways, on my last hc character who is now dead, I was never to purchase items from any vendor, their inventory was always blank. I first started noticing this around level 8. If there is any pertinent info you’d like, please let me know.
https://imgur.com/a/CCkra4e
For whatever reason my upload isnt working here so here is a link to the vendor stash