Reproduction: Attempting to sell a red potion of 9 potency with 9 potency potions in a personal chest for any input amount will yield no output because it cannot find the item.
Bug: Tradeboxes not selling specific items containing meta data
I believe this is a "feature", due to how the meta-data is stored for the potions.
It's a feature that it can't be sold through tradeboxes? I might have caused a misunderstanding -
Basically any potion of the same type and amount of potency can't be sold using the tradebox at all which, I would assume, is because it can't match them properly.
I haven't gone to trying other items with a similar sort of setup, but it wouldn't be surprising if they can't be sold either.
i think the problem is that the potions even how have different strengths. sure you made potency 9 potions but sometimes it depends on your lvl, how good the potion is